I'd ask her to send it as .jpg, not as .dat. .dat is used as meaning "some data", and no program will even try to open it as a picture. All you can do yourself first: save it to your hard disk and rename it from xxx.dat to xxx.jpg (xxx meaning the filename before that dot). But that only works if the content of the file is correct, but it's just the name that's wrong.
Since you don't tell what message you get when opening that text file nor with what program you open it, it's impossible to comment about that. Does it mean you can't open it, or is it just a warning?
Kees
My daughter is sending a photo from Italy and I am getting an error message that Windows Photo Viewer does not support the format (.DAT). I don't believe Windows Photo Viewer is my photo viewing program , it is Windows Live Photo Gallery. In the same document I am getting a code type message trying to open a .txt file. However I have received an email from her just fine. I have tried opening these things with other programs but get the same message: The format is not supported. Does this have to do with an overseas issue? (I am in the U.S.).

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