problem deleteing backup that is corrupt

I have a backup that got cancelled accidentally. I tried to delete the .tib (it is 90gb). Explorer would not allow it, it says it is open in TIH2012. That program is not running. I checked with the task manager. I then deleted the backup thru TH2012. It did not delete the file either. I then shut down all of TIH2012 and rebooted (removing startups with MSCONFIG for both the programs and services. I then tried to delete thru explorer and still get the message that it is opne in TIH2012.
Unlocker does not show it (I assume since it is on a NAS). How do I get rid of it so I can use that space. I need it for a new backup?

Help, any help appreciated.