Problems with KMail after upgrade.

I still have that bug report to do. I'm sorry. It will get done. Meanwhile, I have a problem. I recently did an upgrade for a client of mine. Debian 8.7, TDE 14 (Slávek's repositories), KMail 1.9.10. KMail was being a bit slow downloading the emails the first time he opened it after the upgrade. So he shut KMail down. Opened it up again. Restarted the computer. Rinse and repeat a few times. It is now sending OK (SMTP) but not receiving (POP3). Ideas, please? (He also en route told it both to store the password in KWallet and not to store the password in KWallet, simultaneously.) Given that the problem might be at least partly due to KWallet, can I safely uninstall KWallet? Just reinstalling it might leave the config files the same, and the config files could (perhaps?) be the problem. Lisi