Passwords keep failing

[#1]

FWIW I use Thnderbird for my emails. This morning whenever I attempt to send or receive I am asked for the passwords for my accounts even though the words are saved (tick in request password dialg box). Reinputting the correct paswords makes no difference. What the dickens is up, and how can I cure the problem, please? Message was
There was a problem logging onto your mail server. Your Password was rejected. Account: 'xxxxxx, Server: 'mail.plus.net', Protocol: POP3, Server Response: '-ERR Login failed.', Port: 110, Secure(SSL): No, Server Error: 0x800CCC90, Error Number: 0x800CCC92

[#2]

I've just tested a couple of mailboxes via telnet and can login without problems. Is it one of your mailboxes in particular you are having issues with? If you don't want to post the name in the forum PM it to me and I'll have a look into it for you.

[#3]

Thanks Chris! I have sent a PM.