I have been using K-9 for nine years now.
I use version 5.600 under Android 7.1 on a Sony Xperia Z5 Premium with imap4.
Until two weeks ago I could see email having been filtered to the folder Spam by my IMAP4 server at Ionos.
Then I got a notification about an email that was filtered to the folder Spam by Ionos.
I synced my Spam folder via K-9, but it appears empty.
K-9 states it is synced.
But when I look at my Spam folder via a webclient, Thunderbird or Pegasus Mail I can see all the emails in the folder Spam.
Only K-9 seems to hide its content.
This problem didn’t happen before two weeks!
I phoned Ionos, but they told me that they didn’t change anything and it must be a problem with K-9.
How can I solve this, so that I can see the emails in the folder Spam again?
What might be the problem here?
It doesn’t occur with my other accounts e.g. GMX in my K-9!
The 5.6 version of K-9 hasn’t been updated in some time so a recent change in behavior can’t be attributed to the client proper.
Did you happen to change the folder classes that are synced, or the folder class of your “spam” folder for this account? I don’t have 5.6 handy, but I believe you will find the “poll folders” option in the “fetching mail” settings. Make certain that the folders you want synced are in the classes that you sync.