K-9 has stopped receiving mail, was working OK until a week ago. If I try to receive mail I can see the top line flashing as though mail is being received but nothing is displayed. I can send mail OK. What can I check?
K-9 5.807
Samsung Galaxy A3
Android 8 (I think)
Receiving mail from Sky Yahoo
Yahoo has been transitioning users to OAuth2. With clients that donât support that, including K9, you need to set up/use an âapp passwordâ. I would, however, think that this would impact both your incoming and outgoing, not just one side, assuming you are using their servers for both.
Iâm assuming that you have looked at your mail with another client/webmail and can confirm that you have received new messages.
If yes, then the first thing to try is in â/settings/fetching mail/incoming serverâ select the ânextâ in the lower right and see what response you get. If you get an authentication error it may be the OAuth2 issue. In that case you should be able to find help information on the yahoo site explaining how to do that (itâs also findable in previous forum items).
If thatâs not the issue âŚ
are you using IMAP or POP?
what are your incoming and outgoing server settings (please list separately):
Sounds to me like a hoster offering MX through their domains for customer domains.
E.g., there is all-inkl.com. If you host with them, your mails are fetched from a server like w12345678.kasserver.com. This leads to a certificate mismatch if you are fetching for your own domain (such as mail.example.com) from this server. To circumvent, one can either ignore the certificate warning when fetching from mail.example.com, or one can directly fetch from *.kasserver.com. The username and password is the same either way as the physical machine behind both MX entries is the same.
Other providers known for such issues in the past are web.de, freemail.de and even Yahoo. One used to fetch from protocol specific servers such as imap.web.de while the certificate they used was only issued to pop.web.de. However, I think they fixed this by using proper (wildcard) certificates now.