Thursday, April 18, 2013

MOSS Access Denied – BackConnectionHostName or DisableLoopBackCheck

When attempting to view a MOSS (SharePoint) 2007 or SharePoint 2010 site locally from a Web Front End (WFE) you get an error stating:

"HTTP Error 401.1 – Unauthorized: Access is denied due to invalid credentials."

I have noticed that this happens on Windows 2003/2008 Server SP1/SP2/R2 when using Host Headers and Alternate Access Mappings on a web application in MOSS 2007. If you can access the site from remote machines and cannot access the site from the server itself, then this might be your issue.

These below registry settings needs to be handled while we are trying to access with Host Header and AAM. We need to keep it handy .


If you cannot access the web site locally or remotely from other machines then there is an issue with security on the site and/or possibly a Kerberos related security issue

There are two Method to resolve this issue.

Method 1: Specify host names

To specify the host names that are mapped to the loopback address and can connect to Web sites on your computer, follow these steps:

1. Click Start, click Run, type regedit, and then click OK.
2. In Registry Editor, locate and then click the following registry key:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Contro l\Lsa\MSV1_0


3. Right-click MSV1_0, point to New, and then click Multi-String Value.
4. Type BackConnectionHostNames, and then press ENTER.
5. Right-click BackConnectionHostNames, and then click Modify.
6. In the Value data box, type the host name or the host names for the sites that are on the local computer, and then click OK.
7. Quit Registry Editor, and then restart the IISAdmin service.


Method 2: Disable the loopback check

Follow these steps:

1. Click Start, click Run, type regedit, and then click OK.
2. In Registry Editor, locate and then click the following registry key:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Contro l\Lsa
3. Right-click Lsa, point to New, and then click DWORD Value.
4. Type DisableLoopbackCheck, and then press ENTER.
5. Right-click DisableLoopbackCheck, and then click Modify.
6. In the Value data box, type 1, and then click OK.
7. Quit Registry Editor, and then restart your computer


 


 

If you have a more elegant solution/suggestion – please post a comment… I'll be happy to hear.


...HaPpY CoDiNg

Partha (Aurum)