QuickBooks .qbi file

I've got a user running QuickBooks. QuickBooks creates a .qbi file while it's running that's used to recreate the main .qbw file in case the program crashes. When QuickBooks is shut down the .qbi file is supposed to be deleted.

My problem is that the .qbi file is not being deleted which tags the main .qbw files as "in use" and therefore I can't back them up. Rebooting the machine doesn't delete the offending file.

I can open the processes viewer on the problem machine and manually shut down the qbi process which solves the problem. However this isn't convenient.

Any ideas on how to resolve this? TIA