A file is made up of a filename and a file extension, e.g. explorer.exe which is what displays the data when you open My Computer, Windows Explorer and even your Desktop.
By default, XP hides the file extension. You can undo that and show file extensions as well as hidden files and folders (another lame attempt by Microsoft to protect the user from him/her self).
Open Control Panel then Folder Options and click on the View tab.
Select "Show hidden files and folders"
Uncheck "Hide extensions for known file types"
Click Apply and OK
Now when you click on a file, you will see the filename.ext and can post that info here so we can better help you.
try opening it up in notepad or wordpad or MS Word if you have Office installed. Is it a email attachment by any chance? Or supply the file extension as suggested.
I fixed it….I guess Acrobat adobe Reader was removed from the laptop…So i installd the newest version and it is working now.
Thanks for all your help people.