MOSS search access denied error after .NET Framework 3.5 sp1 installation

Recently we rolled out .NET Framework 3.5 sp1 on our MOSS Servers. During testing, we found out that while crawling the Sharepoint website the following error occurred:

Access is denied. Verify that either the Default Content Access Account has access to this repository, or add a crawl rule to crawl this repository.

To fix the above issue, try the below steps:

• 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
• 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.(Try to re-run the crawl after registry change without restart. Sometimes it may not be necessary to restart.)