Default content access account all errors

After renamed the drive SharePoint Server 2010 working well but when you go in Search service and click on Content sources we aregetting below error.

Unable to cast COM object of type 'Microsoft.Office.Server.Search.Administration.MSSITLB.CGatheringManagerClass' to interface type 'Microsoft.Office.Server.Search.Administration.MSSITLB.IGatherManagerAdmin3'. This operation failed because the QueryInterface call on the COM component for the interface with IID '{0FF1CE14-013A-0000-0000-000000000000}' failed due to the following error: Error loading type library/DLL. (Exception from HRESULT: 0x80029C4A (TYPE_E_CANTLOADLIBRARY)).