Last couple of weeks are crazy as we are working on moving few of our projects to Production.  Not able to post any articles.  But it was helpful as becuase of too much work / deployments I am able to come across many issues and fixes, which i have listed seperately.  I will keep posting the articles based on my experiences over there.

So now, coming back to the story

We have a Huge Content database with Intellectual property of client as documents / Metadata configured on them using External Columns (BCS Models) which we had to migrate to Production.  Search is configured on it.  After moving the site to Production, I came across this error when the Site is trying to generate search results.

System.Runtime.InteropServices.COMException: Illegal operation attempted on a registry key that has been marked for deletion. (Exception from HRESULT: 0x800703FA)

This is not an error specific to SharePoint / Search but it occur happen in .NET applications too which are hosted on Windows Server 2008. The environment i am using is Windows Server 2008 R2.

Ok now to resolve this issue,

Open Group Policy editor on the server (which is hosting the Search Service Application): Start -> Run -> gpedit.msc

Computer Configuration -> Adminstrative Templates -> System -> User Profiles

there will be a setting which says “Do not forcefully unload the user registry at user Logoff” by this this will not be configured.  Enable this setting and it should resolve the issue.

Hope this helps.