If you ever receive the error:
Error: 500 Failed to connect with the search service
when trying to connect to GFI MailArchiver, and in the event log an error about cannot find an IPC file, the reason is most probably a port conflict on port 8019. In my case Intuit QuickBooks had a service running called QBCFMonitorService.exe and that was listening on the same port. Stopping the QB service and marking it as disabled, then restarting the GFI MailArchiver Search Service fixed it for me.
Recent comments