IIS 7.5: 401 Unauthorized Access Error (Keep prompting Username/password)
Yesterday, my ASP.net applications were migrated to Windows 2008 R2 (64bit).
All applications configurations are,
- Developed using .NET v 2.0 & 3.5
- Using 32bit COM/wrapper for ERP access
- Windows Authentication
Without recompiling, applications were migrated to IIS 7.5. Actions taken on IIS for above 3 are, respectively,
All are accessed by our local intranet users. 95% of the workstations using Windows 7. Rest the XP users complaining me they cannot use the applications, in which keep asking the User Name/password. Though they have entered their domain user name and password it did not accept.
After one & half day attempt, I solved this issue. Solution can be found in KB 896861. Folks, if you face the same problem, go head with Method 2 in the KB.
Excerpt from the KB
Method 2: Disable the loopback check (less-recommended method)The second method is to disable the loopback check by setting the DisableLoopbackCheck registry key.
To set the DisableLoopbackCheck registry key, follow these steps:
- Set the DisableStrictNameChecking registry entry to 1. For more information about how to do this, click the following article number to view the article in the Microsoft Knowledge Base:
281308 (http://support.microsoft.com/kb/281308/ ) Connecting to SMB share on a Windows 2000-based computer or a Windows Server 2003-based computer may not work with an alias name
- Click Start, click Run, type regedit, and then click OK.
- In Registry Editor, locate and then click the following registry key:
- Right-click Lsa, point to New, and then click DWORD Value.
- Type DisableLoopbackCheck, and then press ENTER.
- Right-click DisableLoopbackCheck, and then click Modify.
- In the Value data box, type 1, and then click OK.
- Quit Registry Editor, and then restart your computer.