Re: SMTP issue with 421 code
Piotr Wycichowski
10-22-24
Thanks. Finally it occurred certificate problem on mail server. Weird is that the older version of SERP (2021-04-18) was able to sent mail using this server, while newer - not. Suddenly one day our SERP wasn't able to send mails. Our IT support man re-installed certificate and mails started to be sent again.

/Piotr W.
Leave Comment
You can subscribe to notifications for this post by selecting the 'star' icon on the top right corner of the post.
Latest Posts
Lilian Wanyoike
Hi, We have a customer who creates on account receipts against a customer account. Another team is required to allocate these receipts to specific invoice records. Prepayments will not work as t...
15:49 6 Oct 2025
Piotr Wycichowski
Hi! I am not able to run SERP client on Mac (Sonoma), when the folder is outside of Applications. When and why it happens? I know, that some users with the same system haven't such problem. ...
14:54 19 Sep 2025