Using Windows 7 x64. I'm not sure if this issue should be posted here, in the Acrobat Reader forum or somewhere else but here it goes...
This is weird but sometimes when I try to move a PDF file from one folder to other, the move window appears, the "calculating..." messages but it just stays there and the file is never moved. I have to cancel the operation and then close the window. This only happens with some PDF files, not with all of them. Similar problems happen when trying to copy, delete or rename the problematic file(s). I can open the files in Reader or Acrobat without any problem.
Dealing with the file using the command console (the good old MS-DOS window) works.
Also, sometimes I get the wrong miniature preview in PDF files. IE in one file I get the miniature of another file that is not even in the same folder. Maybe this is related to the main problem because right now I'm getting a wrong miniature in a PDF file and that miniature is really from one of those files that refuse to get moved (but maybe just a coincidence, I'm not sure).