Okay, Gary...here is what I would try next. There is an application which I have been using for many years. It is called, "Everything search engine". You can find it here: http://www.voidtools.com/
Download the latest version which is version 220.127.116.111.exe. It is a pretty simple user interface. Then open it and go to: tools>options>Volume tab, then left click on your main drive [probably 'C' drive]. Then go to the General tab and [at least I do this] uncheck "run in the background". I don't need it to run in the background; I just open the app when I need it.
Then, in the search bar just type, ".wpi" without the quotation marks. Be sure that you hit the space bar after you type that. It should bring up all the .wpi files on your computer. Then you should be able to just delete them one by one or if you are familiar with how to do it then you can select them all and then delete them all at once.
Then go to "Start", "Computer" and check to see if you got your 50 GB back.
At least that is what I would do next. I don't know why that would not work. But if not then let me know and we can try something else.
I always create a restore point before I do any operation on my computers. If you have XP then you can go here: http://support.microsoft.com/kb/948247
to see how to create a restore point before trying this operation.
In your next post maybe you could put in what operating system you have. I have been assuming XP just randomly...but I don't really have a clue.
Again, if you feel the need to contact me directly you can email me at: firstname.lastname@example.org
. I have an audible email notifier so I will hear your email come in right away and will try to answer you asap.
"WHAT IF JESUS REALLY MEANT WHAT HE SAID?" - Shane Claiborne