Unable to access hyperlinks in Excel 2010

I have an xls file with several hyperlinks to PDF files on my PC. They did work fine. Just today I was in the file and none of the links will work. A window appears when I click on the link saying this: The operation has been canceled due to restrictions in effect on this computer. Please contact your system administrator. I am an administrator and even logged onto the Administrator account and still could not access the link. On the Administrator account it just said the link could not be opened. Looking for things to check. I am using Excel 2010.