Cannot purchase from Mac App Store ("Connection failure" msg)

Solution 1:

Try this: log out of your iTunes account (within the App Store choose Store > Sign Out), restart your Mac and then try to purchase/download something.

Solution 2:

I FOUND the answer at the link below. The only correction I would add is to do EVERY item that has a blue cross. https://discussions.apple.com/thread/4085819?start=0&tstart=0