Exchange 2010 OWA Search Broken, 0x80041606

Customer with two Exchange 2010 servers, one Hub/CAS and one Mailbox server. Users started receiving an error when searching in OWA: "The action couldn’t be completed. Please try again". I was told that this happened after a power failure (and bad backup batteries), so it sounded like something was corrupted.

The event viewer was also logging an error:

Content Indexing function 'CISearch::EcGetRowsetAndAccessor' received an unusual and unexpected error code from MSSearch.
Mailbox Database: Operations Database 1 
Error Code: 0x80041606

Rebuild the Content Indexes

This was my first step, i took the easy route of stopping the Microsoft Exchange Search Indexer service and deleting the catalogs. These folders are located in every mailbox database folder and start with CatalogData. It is perfectly safe to delete these and then start the service again. After starting the service you will see event viewer entries indicating that it is rebuilding the indexes. You can also run the PowerShell command Get-MailboxDatabaseCopyStatus to see the status. The ContentIndexState column will indicate whether it's Crawling or Healthy.

Repair Symlinks

I saw plenty of articles indicating that the symlinks needed to be repaired, this did nothing.

Reinstall Filter Pack

Ultimately the solution was to reinstall the Microsoft Office Filter Pack on the Mailbox server. This did require a reboot (and yes, I tested it prior to rebooting). Afterwards the search was working as expected.