User having ArchiOffice/EngineerOffice 20xx running on Windows Server 2003 R2 with IIS 6.0 keeps on getting prompted for authentication while trying to log into ArchiOffice. Integrated Windows authentication option was checked initially and now the user is not able to see the ArchiOffice Login screen.
There may be an issue with your Windows authentication.
You can resolve this issue by following these steps:
1. Open your Internet Information Services (IIS) Manager.
2. Go to the Default Website>AO20xx>Admin>Admin Properties screen.
3. On the Directory Security tab, click Edit under Authentication and access control section.
4. On the Authentication Methods screen, uncheck the Integrated Windows authentication option and instead check Basic authentication.
5. Click OK and exit.
This should resolve the issue.