The filtering process could not be initialized. Verify that the file extension is a known type and is correct

This is one of the common issues in the Microsoft Search Server 2008. In the Search Server logs in the Search Server Administration, the following errors are logged:

The filtering process could not be initialized. Verify that the file extension is a known type and is correct

Also the search is not showing the results of some office documents which are having embedded links in it.

Solution:

Installing the Microsoft Office 2010 Filter Packs will fix this problem. This package will add the DLL’s to the machine.

http://www.microsoft.com/en-us/download/details.aspx?id=17062

Usage of this Package:

IFilters are components that allow search services to index content of specific file types, letting you search for content in those files. They are intended for use with Microsoft Search Services (SharePoint, SQL, Exchange, and Windows Search).

Happy Sharing!