Local Activation permission for CLSID {61738644-F196-11D0-9953-00C04FD919C1}

Scenario:
I was investigating an error for my Custom Content Source crawl.I checked ( Event Log > System Node )

I found the following information :

The application-specific permission settings do not grant 'Local Activation' permission for the COM Server application with CLSID {61738644-F196-11D0-9953-00C04FD919C1}

After searching for the CLSID in Registry I found that SharePoint AppPool account needed launching privileges to the Ifilter's 'PDFThunkingSvr' DCOM object and the 'IIS WAMREG Admin service' DCOM object.

Steps:

Start > Administrative Tools > Component Services

1. Look for 'PDFThunkingSvr' DCOM and give access to the database account
2. Look for 'IIS WAMREG Admin service' and give access to the database account
3. Restart Search service ( net stop osearch )
4. After re-crawling , I dont see that DCOM error anymore