Outlook2010 keep asking for credentials after change password feature in OWA is enabled

Hello,

I have enabled the users to change expired passwords by enabling the change password feature in OWA. I have used the intructions from the link below:

technet.microsoft.com/en-us/library/bb684904.aspx

Since then the microsoft outlook keep asking for credentials. Even if i provide the credential it doesnt like it and prompt me to provide the credential. I am using microsoft office 2010 and exchange server 2010 as well. If anyone can throw some light that would be of great help.

Regards