Halachos
Tevillah on Erev Yom Kippur
The Mechaber (606:4) cites the minhag to tovel on erev Yom Kippur. However, the Mechaber adds that we don't make a berachah on such a tevilah. From the fact that the Mechaber felt the need to say we don't make a berachah on such a tevilah, it would seem, that although tevilah on erev Yom Kippur is only a minhag, either because of teshuva or keri, nonetheless, it's more stringent than tevilas Ezra that is performed throughout the year. Consequently, even if one is lenient in regards to tevilas Ezra, he should be stringent when it comes to tevilah on erev Yom Kippur.
By tevilas Ezra, the Biur Halachah (end of siman 88) and Maharsham (Daʼas Torah) both maintain that if one tovels with chatzizas¹ it's ok. However, being that tevilah on erev Yom Kippur is more stringent, the Shlah (cited in Daʼas Torah 606:4) rules that one needs to be particular about chatzizas. The Kitzur Shulchan Aruch (131:6) also maintains that chatzizas are a problem.
We can also be medayek [make an implication] from the Mishnah Berurah that he holds like the above. The Rema writes, that if someone becomes an avel between Rosh Hashanah and Yom Kippur, he may wash himself and tovel on erev Yom Kippur. The Mishnah Berurah (606:26) explains, even though normally during the shloshim period [the first 30 days of mourning] one isn't allowed to wash himself (and Yom Kippur cancels the dinim of shiva and not shloshim), since tevilah on Yom Kippur is a mitzvah, one is allowed to wash himself to make sure to remove any chatzizas. What is the heter to wash, why can't he simply tovel with chatzizas? It must be that for tevilah on erev Yom Kippur chatzizas are a problem. We see that the Mishnah Berurah agrees with the Shlah.
Due to the above, the Mateh Ephraim (606:8) writes, that before toveling on erev Yom Kippur one must make sure to cut both sets of nails. Ideally one shouldn't cut the nails of his hands and feet on the same say, however, bedieved [post-facto] if one didn't manage, the Eleph Hamagen (s.k. 18) writes, that one may cut them both on the same day. The Arizal wasn't particular about the above altogether (see Shaʼarei Teshuva 260:2), and certainly when there is problems of chatzizah one may be lenient.
The Mateh Ephraim also writes, that one should make sure to brush his teeth, and remove any pieces of food that may be stuck between his teeth.
Lighting Long Candles
The Mishnah in Pesochim (53b) teaches, that if one is in a place where the minhag is to light candles on Yom Kippur night, then he should do so, and if one is in a place where the minhag is not to light, then he shouldn't. The Shulchan Aruch (610:1) brings down the above l'halachah. Practically, nowadays, the minhag is to light and to make the berachah “lehadlik ner shel Yom HaKippurim”. The Mishnah Berurah (s.k. 6) explains, the reason we light nowadays, is for sholam bayis [to create peace and harmony in the home], just like Shabbos.
Many men and women light candles and then go off to shul for Kol Nidrei, and only return a few hours later after Ma'ariv. Therefore, one should make sure to light candles which are long enough, so that they are still burning by the time one comes home from shul. If by the time one comes home from shul the candles are out, and one doesn't benefit from them at all, then the berachah made on them may be a berachah levatolah [blessing in vain].
On a regular Shabbos there is a big discussion about what the point of lighting candles is, as in todays world with electric lights normally there is already light. Generally, we take on that since one lights near the Shabbos table, the more light there is the better. On Yom Kippur, however, there is no meal, which makes things slightly more complicated. To avoid this issue, one should either light candles in a dark room, or one should turn off the electric lights, and then turn them on again, and have in mind that the berachah on the Yom Kippur candles is going on the electric lights as well.
Kabbolos [Accepting] Yom Kippur When Lighting Candles
The Mateh Ephraim (610:5) writes, that once a woman lights candles for Yom Kippur, she is forbidden to do any melacha [activity] which can't be done on Yom Kippur, and the inuyim [afflictions] of Yom Kippur start, unless she makes a tanai [stipulation] beforehand. A tanai made in the heart is also ok, however, a woman shouldn't make a tanai unless she really needs to.
The Mateh Ephraim adds, that even if a women doesn't make a tanai, she may still wear leather shoes to walk to shul, as even if she doesn't make a tanai specifically allowing her to do so, most people have in the back of their minds that they will walk to shul with leather shoes.
However, R' Shlomah Zalman Auerbach (Shemiras Shabbos, 44:46) maintains, that the prohibition against wearing leather shoes on Yom Kippur is very severe, no less than any of the others, and unless a women made a tanai specifically, she should refrain from wearing them.
Perhaps we can add, that even if in the back of her mind a woman intends to walk to shul wearing shoes, nowadays, people happily walk around with crocs, slippers etc. all year round, therefore, presumably, even if she had intent in the back of her mind to walk to shul wearing shoes, she never intended to wear leather shoes.
The above, is only relevant if a woman doesn't make the berachah of shehechayanu when lighting, if however, a woman makes shehechayanu when lighting, then even if she makes a tanai it won't help. When one recites the berachah of shehechayanu, he/she accepts the kedushas hayom [sanctity of the day] upon himself (see Shu”t Pri Yitzchok 2:9 and Kaf HaChaim 514:12), therefore, once shehechayanu is said, one may longer do any melacha and the inuyim are now in place, and certainly one is no longer able to wear leather shoes.
Additionally, since one accepts the kedushas hayom upon himself when he recites the berachah of shehechayanu, one may no longer drive to shul for Kol Nidrei. Consequently, if a woman intends to drive to shul after lighting candles, she should make sure not to recite shehechayanu.
The Shaʼar HaTziyon (619:7) cites the Mateh Ephraim who warns, that if a woman has the minhag to recite shehechayanu when lighting, she should avoid reciting shehechayanu a second time when everyone in shuls recites it. She should merely listen, and answer “amen”.
Accepting Upon Ourselves the Kedushas Hayom With Tefillas Zakoh
The Rema (619:1) writes, the minhag is to say Kol Nidrei whilst it is still day. The Mishnah Berurah (s.k. 5) explains, that since Kol Nidrei is a bit like hatoras nedorim [the annulment of vows] and we don't annul vows on Shabbos or Yom Tov, one should try and say Kol Nidrei whilst it is still day.
Based on the above, how can we be accept kedushas Yom Kippur in tefillas Zakoh, and only then say Kol Nidrei? In fact, the Pri Megodim (Eishel Avraham 619:5) writes, that once one has been mekabel kedushas hayom [accepted the sanctity of the day] upon himself, he can no longer say Kol Nidrei. R’Chaim Kanievsky (in a Teshuva at the back of Ishei Yisroel, Teshuva 375) was asked about the above, and he writes, that one shouldn't be mekabel kedushas hayom until after he has said Kol Nidrei.
However, what happens if one is davening Kol Nidrei and it continues on past shkia, and he hasn't yet been mekabel kedushas hayom. Tosefes Yom Kippur [bringing in Yom Kippur early] is de'O'raisa, and according to many needs to be accepted verbally, what should one do?
Seemingly, we have to say, that there is a difference between accepting Tosefes Yom Kippur which is only brings with it an issur aseh, and kedushas hayom which is much more severe (see Dogul Mervovah end of 261, and Shulchan Aruch HaRav, Kuntros Achron 261:3).
The opinion of R' Chaim Kanievsky, that one should only be mekabel kedusas hayom after Kol Nidrei is implicit in the Mishnah Berurah. In one place (607:3) the Mishnah Berurah writes, that the minhag is to recite tefillas Zakoh after eating the seudah hamafsekes, and in another place he writes (619:4) that when one says shehechayanu he should be mekabel upon himself kedushas Yom Kippur. Surely, he was already mekabel kedushas Yom Kippur when reciting tefillas Zakoh? We see like R' Chaim, that one should only accept upon himself the kedushas hayom after Kol Nidrei.
However, we could refute the above, as reciting tefillas Zakoh is only a minhag, and perhaps when the Mishnah Berurah writes one should be mekabel kedusha hayom when saying shehechayanu, he is talking about one he doesn't have the minhag to say tefillas Zakoh.
Kol Nidrei for Women
Strictly speaking, when it comes to hatoras nedorim on erev Rosh Hashanah, there is no reason to differentiate between men and women, however, practically women don't perform hatoras nedorim. Although a women could perform hatoras nedorim in front of three men, even if they are related (see Yoreh Deah 228:3, except for her husband see 234:57), women don't seem to do so. Some women appoint their husbands as a shliach [messenger], however, most don't even do that.
Therefore, the poskim write, that just like the Mishnah Berurah (619:2) writes that when the chazon says the stipulation in Kol Nidrei that any nedorim [vows] made in the upcoming year should be nullified, the tzibbur [congregation] should say it together with the chazon, as the stipulation of the chazon doesn't help for the tzibbur. Similarly, women should also do so, and say along with the chazon.
In regards to the actual recitation of Kol Nidrei, the Mateh Ephraim (619:11) writes, the tzibbur should say it quietly along with the chazon, however, the tzibbur should be careful not to confuse the chazon.
The Shulchan Aruch (Yoreh Deah 211:1) rules, that if one says that the neder he will make shouldn't be a neder, and then he goes ahead and makes a neder the neder is null and void, however, only if one actually spoke it out, if one merely thought in his heart that it won't be a neder, then the neder is binding. The Mechaber then adds, “some say, even if one said it, but he said it quietly, it is considered as if he only said it in his heart”. The Taz explains in the name of the Bach, that if one said it quietly but he was able to hear himself then it is considered as if he spoke it out. However, the Shach argues, that it's clear from the Rosh that it needs to be heard by others as well, and it doesn't help if only the one making the neder is able to hear himself. The Pischei Teshuva and Beis Lechem Yehudah lean more towards the opinion of the Bach, that it's enough that the one making the neder hears himself. See also Shu”t Minchas Yitzchok (9:61) who is lenient. However, the Minchas Yitzchok adds, that since the Mateh Ephraim writes that the tzibbur needs to be careful not to confuse the chazon, the tzibbur should be saying it along very quietly and they may not even be able to hear themselves. Therefore, when performing hatoras nedorim in the morning on erev Rosh Hashanah, they should make the stipulation, that all nedorim made in the upcoming year should be nullified and not rely on the one made in Kol Nidrei.
Based on the above, since the general custom is that women don't say hatoras nedorim, they need to be more vigilant when it comes to hearing the stipulation that they themselves say during Kol Nidrei, as if they can't hear themselves it will be considered devorim shebelev [words in the heart].
Washings Hands After Going to Take Care of One's Needs
One who has the custom to wash his hands three times after being excused may do so on Yom Kippur as well, however, he may only wash until his knuckles. Since this is how he always washes his hands, it's not considered rechitzah shel tanug [enjoyable washing] which is forbidden on Yom Kippur (see Mateh Ephraim 613:5 and Halichos Shlomah 20:25).
The question is, however, what happens if one normally washes his hands every morning four times, three times to remove ruach rah [evil spirits], and an additional time to remove tomei [impure] water (see Mishnah Berurah 4:10 in name of the Gra), may he be lenient on Yom Kippur as well?
It is said over in the name of the Chazon Ish that one may be lenient on Yom Kippur as well (see Ishei Yisroel, Perek 2, He’orah 115).
Appeasing One's Friend on Erev Yom Kippur
The Mishnah in Yoma (85b) teaches, that Yom Kippur doesn't atone for sins carried out between men and his friend (bein adam lechaveiro) unless one appeases his friend. The Shulchan Aruch (606:1) rules accordingly. The Kaf HaChaim (s.k. 3) cites from poskim, that if one doesn't appease his friend, then Hashem won't atone for sins carried out between man and Hashem (bein adam leMakom) either. He explains: If one isn't prepared to ask forgiveness from his friend, then the middas hadin will prosecute and say, this person doesn't care about aveiros, as if he did, then he would ask forgiveness from his friend, so why should Hashem forgive him.
In Siddur HaGra (end of Inyonei Tekais Shofar) a similar idea is brought down from R' Yitzchok Meltzan, “How can Hashem overlook aveiros which are bein adam leMakom, if man which is much less significant doesn't think asking forgiveness is important”. A similar idea is also mentioned in Droshas Chasam Sofer (Vol. 1, pg. 35, brought in chiddushim to Yoma 85b).
However, the Gilyonai HaShas (Yoma 85b) points out that from the Mishnah it seems not like the above. The Mishnah writes: For aveiros that are bein adam leMakom Yom Kippur atones, and for aveiros bein adam lechaveiro, one doesn't receive atonement until one appeases his friend. We see that the two types of aveiros aren't dependent on each other. Practically, it doesn't make a difference, as either way, one must appease his friend.
Speaking Out the Aveirah
The Mishnah Berurah (606:3) cites the Magen Avraham (s.k. 1) who writes, that when one asks forgiveness from his friend he needs to mention what he did wrong. The Bach explains, just like when one asks forgiveness from Hashem he needs to mention the chet [sin], similarly, when one asks forgiveness form his friend he needs to mention the chet. The Mishnah Berurah continues, that where the other person will be offended, he should not specify the details of the injury.
However, the above seems to contradict something it says in Sefer Chofetz Chaim. The Chofetz Chaim (4:12) writes, if one sinned against his friend and his friend doesn't know about it, however, he got shamed because of it, i.e., Reuven spoke lashon horah about Shimon, and the listeners believed what Reuven said, Reuven has to tell Shimon what he did and ask forgiveness. The Chofetz Chaim proves this from Rabbeinu Yonah (Sha'ar 3, Ois 207).
It is said over in the name of R' Yisroel Salanter, that sometimes when one asks forgiveness from his friend, the asking for forgiveness itself is an aveirah, because as long as a person doesn't know that someone spoke lashon horah about him, or that someone embarrassed him, he doesn't feel any pain, but now that he gets told that lashon horah was spoken about him, or that he was embarrassed, then he starts to have agmas nefesh [discomfort]. Therefore, says, R' Yisroel Salanter, sometimes it best to ask for forgiveness without mentioning what one did wrong.
Seemingly, from the Mishnah Berurah that says, that one shouldn't speak out the chet if he knows his friend will get embarrassed it would seem that he agrees with R' Yisroel Salanter, so how can the Chofetz Chaim write in his Sefer Chofetz Chaim, that one must speak out the chet, even if his friend will get embarrassed?
What we have to say is, that in Sefer Chofetz Chaim, the Chofetz Chaim is referring to a case when one knows that his friend won't get embarrassed.
However, the sefer Lev Eliyohu (see Chochma U’Musser pg. 141) brings down a famous story, that upon completion of his sefer, the Chofetz Chaim brought his sefer to R' Yisroel Salanter. R' Yisroel Salanter asked about what he wrote in Hilchos Shemiras Halashon, that if Reuven speaks lashon horah about Shimon, that Reuven must ask for forgiveness and tell Shimon the lashon horah he spoke about him, so that he can forgive him with a full heart. R' Yisroel asked, that by doing so one will cause him agmas nefesh, and how can it be that one must do such a thing. Just because Reuven wants to do teshuva, why should that give him a right to cause his friend pain? The Chofetz Chaim answered, “what should I do, this is what Rabbeinu Yonah says”. It's clear from the above story, that even in case where Shimon will receive agmas nefesh, by being told what was said about him, even still the Chofetz Chaim held one is supposed to tell him. This seems to contradict what he writes in Mishnah Berurah?
There is a sefer written by R' Avraham Rosenberg called Tenuvas Sodei, and at the back of the sefer he brings ten letters which were written by R' Naftoli Amsterdam to R' Yitzchok Blazer of Peterburg. In the last letter he discusses the above and he brings a Shu”t Maharit (2:8 d.h. hacnoh) which deals with asking for forgiveness from a friend and he writes: וכ"ת הא קמ"ל דאע"ג דחבירו מוחל לו בסתם בלא הודעה סגי ליתא דודאי אין זו מחילה דמי ידע דמחיל “Perhaps you will say that it is coming to teach, that even if one forgives his friend without knowing what he did it's enough, the above is not true, and certainly such a thing is not considered forgiveness, as who says he really forgives”. It's clear from the Maharit that one has to speak out the chet, which seems to contradict the Magen Avraham? R' Naftoli Amsterdam suggests, that the above doesn't necessarily contradict the Magen Avraham, as perhaps there are three levels of asking for forgiveness, 1) Asking without mentioning any aveirah, and not specifying that an aveirah was committed against any particular person, 2) Mentioning that an aveirah was carried out against a particular person, but not mentioning what, 3) Mentioning the details of the aveirah and against who it was carried out against. And everyone agrees, that one doesn't need to do level 3, and when the Maharit said one needs to speak out, all he means is level 2.
Asking Forgiveness From Someone Who Will Be Saying Tefillas Zakoh Anyway
It's well known that in tefillas Zakoh we mention that we forgive anyone for what they may have done to us. The question that has bothered me for many years, is, that if we know everyone forgives us for our misdeeds in tefillas Zakoh, is there really a need to ask forgiveness from him in person as well? The simple answer would be, who says he will be saying tefillas Zakoh. But lets say one knows that his friend will, is there still a need to ask for forgiveness?
The Mateh Moshe (end of siman 848) writes, that the actual going over to someone to ask him forgiveness, and the fact that doing so is extremely embarrassing and uncomfortable, that itself acts as a kaporah [atonement]. A similar idea is mentioned in the name of R' Itzel Peterburger (see Moʼadim U’Zemanim 1:54).
Proof to the above, can be brought from a famous Gemara in Yoma (87a). The Gemara relates, that a certain butcher sinned against Rav, and he never came on erev Yom Kippur to ask for forgiveness. Consequently, Rav went and made himself easily available to the butcher to make it easier for him to ask forgiveness, however, the butcher ignored and he still never came, consequently the butcher died. The obvious question is, why didn't Rav just forgive him and end of story, why did he specifically want that the butcher to come to him? We see, that even if Reuven forgives Shimon his friend, Shimon still needs to ask forgiveness from Reuven, as the embarrassment and discomfort in doing so, is itself a major part of the kaporah.
However, the above proof can easily be refuted. Tosfos Yom HaKippurim on the above Gemara writes, that when the butcher sinned against Rav and was mezalzel [cheapened] in his kavod [honor], Rav thought that he may have also been mezalzel in the kavod of the butcher. Subsequently, when the butcher never came to ask for forgiveness on erev Yom Kippur, Rav thought that perhaps the butcher thought that Rav was in the wrong more than he was, and that Rav should be coming to him, therefore, Rav went to him. According to this peshat, the proof falls away.
Moreover, the Gemara in Yoma (23a) writes, it's forbidden for a talmid chocham to be mochel [forgive] on his kavod, unless the one who was mezalzel in his kavod asks forgiveness in person. The above is brought down l’halachah (Yoreh Deah 243) that if one embarrasses a talmid chocham in public, the talmid chocham isn't allowed to forgive, unless the perpetrator asks for forgiveness from the talmid chocham in person. Therefore, perhaps Rav thought he wasn't allowed to forgive unless the butcher asked forgiveness from him in person. Accordingly, we can't bring any proof from the above Gemara to a case of someone who isn't a talmid chocham.
Regardless, the svora [logic] of the Mateh Moshe that the discomfort and embarrassment of asking forgiveness is part of the kaporah still stands.
Tefillas Zakoh
The Shulchan Aruch (607:1) rules, that one needs to say viduy in Mincha on erev Yom Kippur before eating the seudah hamafsekes. However, it's well known, that the Ramban held, that one should say viduy after the seudah as well. In fact, the Ramban held, this viduy is the main mitzvah of viduy, and it should be done just before Yom Kippur, so that one enters the day of Yom Kippur with just having done teshuva and not committing any sins in-between (see Shulchan Aruch HaRav 607:2), the only reason we say it earlier is because we are worried about tiruf hadaʼas (something may go wrong in the seudah hamafsekes and one will end up not saying viduy).
The Mishnah Berurah (s.k. 1) citing the Shlah writes, that it's fitting for one to be stringent and to do the above, and this is partly why we say viduy in tefillas Zakoh.
R' Moshe Sternbuch (Teshuvos V’Hanagos 2:300) writes, that if one only arrives in shul just before shkia and there isn't time to say the entire tefillas Zakoh, he should at least say,אנא ה' חטאתי בשוגג עויתי במזיד פשעתי במרד ובמעל, or some other nussach of viduy, and say it whilst bending over, as according to the Ramban, this is the main mitzvah of viduy.
Therefore, one should do his best to come to shul early enough so that he has time to say viduy before Kol Nidrei, and ideally with enough time to say the entire tefillas Zakoh before Kol Nidrei.
Viduy for Women
From the Rishonim it's clear that women also have an obligation to say viduy on Yom Kippur (see Rambam, Hilchos Teshuva 2:7, Chinuch, Mitzvah 364 and Yeraim, Zemanim 121). The truth is, it's very logical, as do only men need atonement and not women?
However, the Kaf HaChaim (607:4) cites the Yafeh Lev who writes that he never heard of a minhag for women to say viduy.
R' Chaim Kanievsky (Ishei Yisroel 46:54) also writes, that saying viduy ten times on Yom Kippur is a minhag, and it's possible that women never had such a minhag. See there, where he is in doubt if women need to say viduy on erev Yom Kippur.
However, from the lashon of the Tur (607): כל אחד ואחד צריך להתוודות אחר תפלתו קודם שיאכל סעודה המפסקת – “Each and every person must recite viduy after davening before eating seudah hamafsekes” it would seem that women should say viduy.
Viduy Whilst Standing Not Leaning
The Shulchan Aruch (607:3) rules, that one must say viduy whilst standing. The Mishnah Berurah (s.k. 10) explains: דהכי הוי דרך הכנעה טפי ומתודה בלב שלם – “doing so, shows more subjugation and helps one do it with the proper heart".
The Mishnah Berurah adds, that it's also good to recite viduy whilst bowing, like what one does when saying Modim. If, however, one finds it difficult to do so, the Shaʼar HaTziyon (s.k. 6) writes, it's enough if one simply bends his head.
The Mishnah Berurah also writes, that one should make sure no to lean on anything during viduy, to the extent that if the item would be taken away he would fall. Bedieved if one did, the Pri Megodim writes tzorich iyun [it's not clear] if he needs to repeat viduy again or not.
The Imrei Emes asks, how is it possible to entertain a possibility that if one recites viduy whilst leaning that he should need to repeat it, the Kohen Gadol would lean with all his strength (kol koichoi) on the animal whilst saying viduy, so how can it be meʼakev [integral]? (See Mikraei Kodesh on Yomim Noraim 57).
Perhaps we can answer, that when semicha itself is a mitzvah de’O'raisa then certainly leaning isn't a problem, however, nowadays semicha isn't de’O'raisa, therefore, perhaps leaning is in fact a problem.
Nonetheless, the Birkay Yosef (131:8) rules, that an elderly person or someone who is ill may recite viduy whilst leaning. This is how the Steipler was noheg, when he got older and found it difficult to stand without leaning (Orchos Rabbeinu Vol. 2, pg. 203).
If one can't even stand whilst leaning, one may say recite viduy sitting or even lying down (Shabbos Shabboson 47).
Viduy Before or After יהי רצון
The Mishnah Berurah (607:16) writes, that those who normally recite יהי רצון before אלקי נצור should also recite יהי רצון before viduy. The Gaon, however, maintains that אלקי נצור is part of shemonah esrei and one should only say יהי רצון after אלקי נצור. Moreover, the Imrei Noam (to Berachos 3b) writes, that according to the Gaon, once one says יהי רצון it's as if he has taken three steps back, therefore, certainly one shouldn't say יהי רצון before reciting viduy. He writes there, that if one says יהי רצון on Yom Kippur before reciting viduy, it's considered as if one said viduy not as part of shemonah esrei. See also Chayei Adam (144 :9) who rules like the Gaon that we say viduy before reciting יהי רצון.
Answering to Devorim Shebikdusha In the Middle of Viduy
The Mishnah Berurah (607:11) writes, that to answer to kaddish and kedusha, one should stop even in the middle of אשמנו.
The Mishnah Berurah (122:1) also writes, that once one says יהי רצון, he may answer to kedusha. He also writes (s.k. 3) that if one doesn't have time to say יהי רצון, he may still answer, but it's best to say the יהי רצון first.
Therefore, the Luach Eretz Yisroel (Dinei Mincha l'erev Yom Kippur) writes, that even those who follow the Gaon, if they hear kedusha in the middle of viduy, they should say יהי רצון first.
However, in the Sefer Halachos HaGra U’Minhogav (94) it's written, that if one says at least,אבל אנחנו ואבותינו חטאנו, he fulfills the main mitzvah of viduy, therefore, if one has said at least that, then he can say יהי רצון and answer to kedusha. However, if one hasn't yet fulfilled the main mitzvah of viduy, then he should shouldn't say יהי רצון, and he should stop, listen to the chazon and be yoitsa with shome'a k'oneh [listening is equal to speaking]. He concludes, that he hasn't seen this din mentioned anywhere. However, we brought that certainly according to the Mishnah Berurah one should say יהי רצון if there is time, and even according to the Gaon the Luach Eretz Yisroel writes that one should say יהי רצון in order to be able to answer to kaddish and kedusha.
What To Do if One Forgets to Say המלך הקדוש, and He Has Already Finished Shemonah Esrei with Viduy
A number of years ago, there was a story with someone who davened Mincha on erev Yom Kippur, with viduy and then he realized that he forgot to say המלך הקדוש. He went to R' Shlomah Zalman Auerbach (Halichos Shlomah, Tishrei 4:1) to find out what to do, and he ruled, that he should repeat shemonah esrei, without viduy. The Shevet HaLevi (6:73) also paskens this way, and writes, even though the shemonah esrei is in vain, since viduy is something that is recited after shemonah esrei, even if the shemonah esrei is in vain, the viduy isn't and there is no need to repeat.
The Shevet HaLevi proves from a Gemara in Avodah Zorah that viduy is considered something which comes after the completion of shemonah esrei. The Gemara says, even though one should daven for his own needs in the berachah of שומע תפילה, if one wants to add additional supplications after he has finished davening, then he can even say the entire seder avodah of Yom Kippur. Rabbeinu Chananel has the girsa [text], the seder viduy of Yom Kippur. We see that viduy is considered something which is said after shemonah esrei.
Havdolah for Women on Motzei Yom Kippur
It's very common, that women return home straight after Neilah, or they stay home to watch the kids, and it's hard for them to continue fasting once it's already nacht, and to wait until their husbands come home. Seemingly they have two options, either to make havdolah themselves, or to only drink water (like we find one is allowed to do on a regular motzei Shabbos 299:1). However, the Brisker Rov (chiddushim end of Yoma) suggests that perhaps motzei Yom Kippur is different to motzei Shabbos. On motzei Shabbos, the issur to eat before havdolah is because one shouldn't eat before havdolah, therefore, one may drink. On motzei Yom Kippur however, it may be that the dinim of the inuyim [afflictions] stay in effect until one makes havdolah. The Eleph HaMagen (to Mateh Ephraim 624:4) cites the Shoel U’Meishiv who rules that if one is thirsty, he may drink on motzei Yom Kippur before havdolah and even before Maʼariv, however, R' Shlomah Zalman Auerbach (Shemiras Shabbos 62:59) maintains that one shouldn't drink until after he at least says ברוך המבדיל בין קודש לחול or אתה חוננתנו.
The Mateh Ephraim (624:7) rules that women shouldn't make havdolah themselves, even when Yom Kippur falls on Shabbos, and certainly when it falls during the week. The Minchas Yitzchok (8:51) explains, that on motzei Shabbos there is more reason to say women are obligated in havdolah as we make a hekesh [juxtaposition] between the words of זכור and שמור, and on Friday night women are obligated in kiddush on a de’O'raisa level. On Yom Tov however, kiddush is only derabonon (see Lechem Mishnah, Hilchos Avodah Zorah 12:3, and Minchas Chinuch, Mitzvah 31 who are in doubt as to whether women are obligated in kiddush on Yom Tov. Although R' Moshe, Igros Moshe, Orach Chaim 4:100, and Shulchan Aruch HaRav rule they are, from R' Akiva Eiger, hashmotas to siman 1, it's clear that really they are exempt and they just accepted it upon themselves.)
Nonetheless, if they can't hear havdolah from a neighbor, and it's difficult for them to wait, the Shevet HaLevi (4:54:7) writes they can make havdolah themselves, as strictly speaking we rule that women are obligated in havdolah and they can make it themselves. Although she will have to drink the wine, it's not a problem, as although women normally refrain from drinking havdolah wine, there is no real reason behind it, therefore, halachically it's perfectly ok for her to drink.
However, she shouldn't make a berachah on candle, as even on motzei Shabbos it's a machlokes, and she can hear it from her husband later, so why enter herself into something which is a big machlokes.