[regnatarajan]

I found this thread while looking for a solution to this problem with Blackberry accessing a Sharepoint site. With Windows Sharepoint Services 3, it's easy to get past this error message if you're willing to allow plain text passwords.

1. Load Sharepoint Central Administration.
2. Go to Application Management | Authentication Providers
3. Select the appropriate web application from the drop-down list at the top right (don't skip this step or it won't work).
4. Click the authentication provider in use (probably Default).
5. Under IIS Authentication Settings, put a tick in "Basic authentication (password is sent in clear text)".
6. Save your changes and test.

Cheers,
Reg Natarajan