Yes, I've read and done the steps listed here with no results: Disable 'Save changes' dialog in Adobe Reader

Basically what happens is with certain pdf documents, whenever I try to close them, it prompts me to save changes. This baffles me, as per their FAQ, Reader can't save anything, and I didn't make changes to the document in the first place. The one cause I could think of would be that the documents may not have been created with Adobe software, and as such may not write the pdfs in a way that makes Adobe happy.