Hi,
***THIS IS NOT A PROBLEM BUT A SOLUTION***
I followed: https://support.configserver.com/en/kno ... -extension
Editting: /usr/mailscanner/etc/filename.rules.conf and (in my case) commented:
#deny \.cer$ Dangerous Security Certificate (according to Microsoft) Dangerous$
And added just after "# These are very dangerous and have been used to hide viruses"
#NubeNinja
allow \.cer$ - -
allow \.key$ - -
allow \.req - -
And worked as a charm if the files were attached normally but if I zipped the contents then I received and email like this immediately:
Warning: E-mail viruses detected
One or more of the attachments...
THE SOLUTION:
You have to edit /usr/mailscanner/etc/archives.filename.rules.conf in exactly the same way.
After that, you can have any extension you like/need attached as is or zipped.
This is a workaround for: https://support.configserver.com/en/kno ... r-filetype
Hope it helps someone.