Manual Reseed of Exchange Content Index

I recently ran into an issue where a mailbox database content index was in a failed state after the Exchange 2010 server had a power outage. Not too big of a deal since it was in a remote site that was hosting only passive databases for disaster recovery.

Normally for a passive copy, you run the following command and all is good:

Update-MailboxDatabaseCopy -Identity DBName\ServerName -CatalogOnly

However I got this error:

A source-side operation failed. Error An error occurred while performing the seed operation. Error: An error occurred while updating the search catalog files from server 'XXXXXXX'. Error: A transient exception from Exchange Search was encountered. Error: Catalog was not paused for indexing on database dbGUID.

There were only a couple of search hits for this specific error about pausing indexing and they really only indicated it was an internal process as part of the catalog reseed. There were no useful errors in the event log.

I tried a few different variations with no success:

• initiate from passive
• initiate from active
• suspend passive copy before updating catalog
• remove catalog files on passive before starting
• force AD replication in case replication lag was causing an issue

Finally, what worked was the following:

1. Stopped the Microsoft Exchange Search Service on both the active and passive copies.
2. Deleted the catalog folder on the passive.
3. Manually copied the catalog folder from the active to the passive.
4. Started the Microsoft Exchange Search Service on the active.
5. Started the Microsoft Exchange Search Service on the passive.

After following this process, the content index on the passive copy is good.