With the CRM 3.0 Client for Outlook, you may experience prompting for credentials occasionally. Normally, CRM 3.0 should be using Windows Authentication and as a logged-in member of the domain you shouldn’t ever be prompted for credentials to access CRM (either via the web or Outlook client). To resolve this occasional prompting, there are usually 2 things that must be done:
1. Check to ensure that the URL used for accessing CRM from the Outlook client is a member of the Intranet Security Zone in Internet Explorer. To do this, open a new Internet Explorer window and type the URL in the address bar. Check the right hand side of the status bar at the bottom of the screen where the zone is displayed. If it is not in the Intranet Zone, please add it in your Internet Options.
2. Change the following registry entry to “0” instead of “1”.
After making these modifications, clear your temporary internet files and cookies.