If you are having problem logging into the webmail system, make sure you are using the full e-mail address (i.e. bob@smith.com rather than just bob). 

Additionally, please ensure that you have included a trailing slash on the end of the webmail URL. 

For example . .  

Correct: http://www.yourdomain.com/webmail/

Incorrect: http://www.yourdomain.com/webmail 

If this does not solve the problem, please open a ticket explaining your problem.  Be sure to include the username and password of the POP account so that the technician can troubleshoot the issue.