Unfortunately Adobe doesn't offer the ability to do so from within the program, and I'm not sure exactly where the history for Adobe Reader is kept. However, I use the free program CCleaner, which will clean your computer of junk and temp files, including the histrory lists of most major programs. (It recovers 100MB+ of space for me daily.) If you only want to wipe out the Adobe history list, don't worry...it lets you customize what you want it to clean by unchecking what you want left alone. (Leave only "Adobe Acrobat Reader" checked.)
Hope this helps,
John
How do I delete the recent files listed in the file menu of the free Adobe reader 6.0?

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