Mail not working with outlook express

[AcComp]

I tries everything I can think of searched these boards etc. Nomatter what no email on the domain works with outlook. I can check it through cpanel but not get to outllok express here is the error:

There was a problem logging onto your mail server. Your Password was rejected. Account: '******@*******.net', Server: 'mail.*****.net', Protocol: POP3, Server Response: '-ERR Authentication failed (bad password?)', Port: 110, Secure(SSL): No, Server Error: 0x800CCC90, Error Number: 0x800CCC92

Of course I replaced names with ****

[dalem]

could be a number of things

is it for just one domain or all of the domains on the server

[tuxdesk]

If it is affecting to whole server Please check WHM
Main >> Service Configuration >> Exim Configuration Editor
Uncheck the box -- Always set the Sender: header when the sender is changed from the actual sender.

[myusername]

Some users experience this depending on their ISP blocking port 25.

Tell your user to keep their incoming mail server as mail.domain.com and change their outgoing mail server to mail.theirISP.com where mail.theirISP.com is their ISP's actual SMTP server, of course, in most cases you will not know what that is so you have to tell you user if they do not know what their ISP's SMTP server is, to ask their ISP.