Authentication Error with SharePoint Application which uses Host Header on the Server firm

 

 

Reason: The main reason for this issue is Windows includes a loopback check security feature that helps prevent reflection attacks on your computer. Therefore, authentication fails if the FQDN or the custom host header that you use does not match the local computer name as the system blocks the authentication procedure while resolving the host header given to the web application.

To resolve this issue, a modification must be done to the server's registry to specify the host name. To specify the host names that are mapped to the loopback address and that can connect to Web sites on your computer, follow these steps:

Solution:

§  Click Start, click Run, type regedit, and then click OK.

§  In Registry Editor, locate and then click the following registry key: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Lsa\MSV1_0

§  Right-click MSV1_0, point to New, and then click Multi-String Value

§  Type BackConnectionHostNames, and then press ENTER.

§  Right-click BackConnectionHostNames, and then click Modify

§  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.

§  Exit Registry Editor, and then restart the computer