Do you have any formulas or macros in your files? If not you can try to open it using WordPad or other similar program. But it works only with the data.
Have you tried open&repair command? It might fix the problem.

Also look at this discussion, it is possible that here you will find something.
https://social.technet.microsoft.com...itproappcompat

Another way is uninstall all add-ins if any.