qmail

Raised as a usability problem by 6 people on Hacker News over 11 years (2009–2019), in 6 threads.

People raised many different problems with qmail, but no single problem has yet been raised by 3 people in 3 different months and threads.

Unreviewed issues were grouped by machine: Claude Haiku labelled each comment as a usability complaint, named what it's about and summed up the problem in a line, and a small model grouped similar problems. Nobody has checked them by hand. Expect mistakes.

The newest 6 complaints

Running a reasonable mail server required manually applying many patches to the sources2019-08-21
Needs patches to do things Postfix does out of the box2019-08-20
Totally unusable without a lot of fiddling to get the right patches2017-08-28
Must compile from source and apply third-party patches to get features2015-03-06
Checking configuration means cat'ing many separate files back and forth2010-10-10
Hard to use for someone just wanting to send mail2009-05-28