ftiattachmentworker.exe does not process attachments.
WORKAROUND
Stop the Archive Full Text Index Service.
Stop the Archive Full Text Search Service.
Verify the ftiattachmentworker.exe and ifilterhost.exe processes are not running.
Browse to the \ArchiveManager\Index\Attachment folder
Check if there is a *.lock file.
Please delete this *.lock file and start up the archive manager services again.
The lock file should not exist when all the services and processes are not running.