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While at shul for mincha the other day, the chazzan began to say Kaddish after finishing *Chazarat Hashat"z' (Shemoneh Esreh repetition). Ata bout the point people answered Yehei Shmei Rabba, people yelled at him - "You forgot to say Tachanun!"
The Chazzan answered - "I forgot. Too late, now" and continued with the rest of Kaddish and no one said Tachanun.
What should be done in such a situation?
- Continue Kaddish without Tachanun, as we had done?
- Finish Kaddish, then say Tachanun then aleinu without repeating Kaddish?
- Stop Kaddish in the middle, say Tachanun and repeat Kaddish, then Aleinu?
Other factors to consider:
- Someone had told me that if you say Mincha past a certain time when it is close to nightfall (I'm not sure exactly what the break point is - I guess about 10 minutes before tzet?) then you wouldn't say Tachanun, anyway?
- Does it matter how much of Kaddish had already been said to decide if to go back to say Tachanun or not?