.Ai open blank in Photoshop and Preview. IS the file corrupt?
There are numerous reasons it may not open properly in any number of apps. The important thing is if it opens correctly in Illustrator (as Spanky already stated above).
Off the top of my head, it could be as simple as everything in the AI file could be on a hidden layer in AI.
That's not it. While you're correct about the PDF Compatible option, when you try to open it in PS, Acrobat, Preview, etc. it doesn't open as a blank document as mentioned in the original post—it opens as a paragraph of text.and it could be that the Ai file was saved w/o the option to make a file that is PDF compatible. Acrobat and Ps can only read Ai files saved with this option turned on.