Opening Files from Acrobat.com

I am running Adobe Acrobat XI Standard on Windows 7 Enterprise. Until recently, I was able to open Acrobat.com files from within Adobe Acrobat. Now, attempting to open files from Acrobat.com gives me the message: "We're having trouble reaching the server right now. Please check your network connection and try again." I waited two weeks, but the message has not gone away. I just reinstalled Acrobat this morning, and that also has not helped. Any suggestions?