I just bought and downloaded Sketchbook pro. It is a file named Autodesk_Sketchbook_Pro_v6_Multilingual_WIN_32bit
but there is no extension and I don't know what to do with it. Should I rename it with a .exe extension?
From your description, it sounds like you have enable Hide extenions for known file types under Windows Folder options here. You should see the .exe extension if you disable that option.
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