OH tech question
OH works best with a Chrome browser. Firefox works, too.
If you only have Explorer, try going up to the http://www line and at the far right end of that line you should see a looking glass (search feature) and a piece of paper (that might be colored blue) that looks like it has been ripped in half. Click on that blue ripped paper icon and then try again. You might have to cancel out of the box and open a new one.
Good luck.