Font file remaining in _TempLaunchFolder after Setup

Upon Setup completion, one file is remaining in the _TempLaunchFolder, and that is the Font file used by the Setup:
Microsoft Sans Serif_1.TFT

I even try to manually delete the files in the OnShutDown Action with no luck:

File.Delete(_TempLaunchFolder.."\\*.*",true,false, true);

The only way I can delete it is to schedule it for DeleteOnReboot.

Is there some super-secret way to delete this file without having to reboot? (SUF 9.2).

Thanks.