Prefetch file causing a problem.

Windows XP pro. When I run a security program to delete data I am getting an error in C:\windows\prefetch\sfx13.tmp. I didn't get this until today. I recently ilnstalled Media player 9 but I can't remember if I have run the program since. Is it safe to delete this file sfx13.tmp? I googled it and found nothing that made any sense.

Edit:
More info. I am using Internet Washer 3.05. When I run it using the delete Temp files option my Zone Alarm comes up sfxC.tmp is attempting to access the internet. Whether I allow it or not I get a prompt "Do you wish to uninstall this Software" if I say yes I get a dos box that says C:\windows\command on the title bar and amessage in dos that says the software has been removed. When I reboot and and run Intenet Washer again I get a different sfx file (the letter after the sfx keeps changing). I am going to virus scan and run spybot.