Gregory's Server@doerk @hacks4pancakes I was sending a digitally signed purchase order in a digitally signed email to the official distributor of the company everyone uses for those kinds of fittings.
Their email configuration couldn't handle it, replacing my whole email with a smime.p7m file, and I had to send it again with signing disabled...
@pkraus @hacks4pancakes That‘s not unusual. Most people don’t know how to handle signatures and keys. That’s the reason why most emails are still sent unencrypted.