That type of problem is usually caused by interference from a non-
compatible antivirus program. Which antivirus are you running?
As a minimum, email scanning in the antivirus must be turned off,
although that may not be sufficient to eliminate all bad effects.
In a worst case scenario, your antivirus may need to be uninstalled.
Email scanning in any antivirus must be disabled, for reasons
If no improvement after disabling email scanning, consider upgrading
to Windows Live Mail, because it is less prone to suffering bad effects
from overly intrusive antivirus programs:
Gary VanderMolen, MS-MVP (Mail)
"Ceramo" <Ceramo@xxxxxx> wrote in message news:8E83BA21-FD12-444A-8414-7BEC77CF4C96@xxxxxx
> Even though I am sending and receiving emails, after receiving and sending I
> continually get a pop up box asking for username and password, I can just ok
> it, and keep doing it then ' checkbox is ticked. After that an error box for
> windows security comes up with Account: 'mail.bigpond.com (1)', Server:
> 'mail.bigpond.com', Protocol: POP3, Server Response: '-ERR a user name MUST
> be entered', Port: 110, Secure(SSL): No, Server Error: 0x800CCC90, Error
> Number: 0x800CCC91.
> How can I get rid of this box always coming up, I do seem to receive and
> send reasonably well?