There are no differences between the files, so a .txt file is the same under XP as it is under Vista, and likewise for .doc, .jpg, etc. In fact there are only a couple file types natively supported by Vista that aren't under XP, such as the new pdf-competition .XPS. However, you didn't mention what the file types are, what problem occurs, or the associated error message, if applicable, so it's hard to tell what the root of the problem is. Fill in the details and we'll see what we can do to help.
John
ive tried putting files from my vista computer to my xp computer by burning data on a cd, transfering files to an external hard drive through usb, and networking. none of them worked for me, are any three of these even possible? can xp read ANY files that come from a vista computer?

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