I have a SharePoint WFE that is using NTLM authentication with anoyomous access enabled and windows authentication enabled via IIS7. When my users browse to the portal (MOSS 2007) and click the login link, they are able to sign into the portal with no problems automatically which pulls their login from windows authentication. However, 10 minutes later they are presented with a username/password prompt that pops up. When they try to login by typing (username: domain/username, password: password) they are unable to. If they click cancel the portal page results into a blank white web page. Once they close the browser and bring it back up and try to click the login link again they are again prompted for username/password. The strange thing is if they wait a few minutes they are able to log back into the portal with no problems automatically. It seems like the users are losing their login credintials, which is prompting them for their login credentials, but if they wait a few mintues they can sign in again with no problems. Very strange. Usually when something like this happens I have the users run gpupdate /force on their workstations to update their GPOs. This usually helps, but nothing seems to be working to fix this problem. Has anyone experienced this issue, and if so how were you able to overcome this? I figured it might have been HBSS, but I disabled that on both SharePoint and the SQL servers to test, still getting prompted. Made sure the portal is trusted intranet site and made sure that IE7 is set to allow for automatic login. Checked and double checked the service account to make sure the password is correct. Any help on this issue would be much appreciative. Thank you for your time, v/r JShidell