How to fix so that the files do not come archived?

Question

Mail server

Good afternoon.
There is a mail server: MDaemon (32-bit) v18.5.1.
When sending emails from our domain to other domains, attachments come in a zip archive whose name is gibberish in Russian. At the same time, attachments in letters of recipients can be archived and not archived, even to the same recipients, changing almost every day, every hour. At the moment I can not attach an example of an attachment, and test ones come without an archive. An example of the name of the incoming .zip attachment is "NRVER ON GBNMYUL GU 25 MBYUP.xls.zip", after unpacking the folder "NRVER ON GBNMYUL GU 25 MBYUP.xls" appears, it contains an undamaged original file that was sent a "report on calls for January 25 .xls".

Answer 1

look here for your settings. probably worth it - "archive outgoing mail". uneven behavior - probably depends on the size of the attachment. if more than something, then archives.
clumsy attachment name - old multi-encoding problem. utf8, cp1251, koi-8r