Hi 3cats,
> Adding an extension and opening within
the program isn't working.
As Bill said, the resource forks (and some metadata) of the files have been lost so the files have been corrupted in some sense. Because Apple deprecated the use of the resource forks, newer version of M$ apps shouldn't need resource forks but a classic version of one of the apps may have created a file that is corrupt without the resource fork. That's a little hard to address.
I recommend trying to open the file with a Windoze version of the correct app. If you get something you can work with you should save the result. Even back in the classic days, M$ apps for Mac had to interoperate with the PC versions of the apps. Therefore, after you get something workable in a Windoze version of an M$ app, you should be able to open the saved document with a Mac version of the app. Of course there's no guarantee that the Windoze version of an M$ app will be able to open one of the corrupted documents but M$ is more concerned with making the Windoze versions of the apps appear to be robust.
--
Gary
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