What would cause me to get the following error message when I try to open some .doc or .docx files in Word 2010 64bit which is on one of my PCs?

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Word experienced an error trying to open the file.
Try these suggestions:
* Check the file permissions for the document or drive.
* Make sure there is sufficient free memory and disk space.
* Open the file with the text recovery converter.
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There does not appear to be any problem with the files themselves because I have no trouble opening them in Word 2007 on my other PC.

It does not appear to be a permissions problem because I am able to open them through my network from my other PC (Word 2007).

I have no trouble opening most .doc and .docx files in Word 2010.

The files I'm having trouble with in Word 2010 are all resumes created by other people on their own PCs and then emailed to me. None of these files were created by me. Each resume was created by a different person and no two of them have anything to do with each other. (9 resumes from 9 different people using 9 different PCs.) I can't open any of them in Word 2010. I can open all of them in Word 2007.

Thanks for any clues!
Peter