I am using
gnus to read mailing lists from an
imap account. For some reason some (really) new messages are marked by Gnus as ancient, i.e. with O, they appear in the summary buffer together with the rest of the new messages when I enter a group first time, but they will disappear once I leave the group. Also the navigation commands, e.g. next-article, skip them.
Which settings control the expiration and navigation on such things?
I solved it partially by setting
(quote never) in
emacs customization. Now the navigation commands go to any next article in the summary. But the question how to not let them expire is still open.