Excel 2010 saving as PDF problem

Hi guys!
Here is my situation, I have Windows 7 Professional 64-bit setup on three computers with Office 2010 64-bit.
I downloaded and installed Adobe Reader X on those computers. When I make a new Excel 2010 worksheet, I don't have any problem saving as a PDF, as well as other "simple" worksheets. In an Excel 2010 worksheet with multiple tabs, I need to save one tab to PDF file.
But then, I get this error message: Microsoft Excel–Document not saved. The document may be open, or an error may have occurred when saving. Then after trying to save a few times, it appeared to work.
However, when I tried to open the saved PDF file, I receive this error: Adobe Reader -There was an error opening this document. This file cannot be opened because it has no pages. I have uninstalled/reinstalled Adobe Reader X. No change. Any help please.
