If you receive an error that the the Provider may not be installed correctly when attempting to link to an Excel or Access file, the download should resolve the problem.
http://www.microsoft.com/en-us/download/details.aspx?id=23734
This download contains the data access driver for Office. These drivers should be installed already if you have MS Office 2007 installed, but in some cases they may not be installed or may have been corrupted.