MonoDevelop opens 2 empty windows since upgrading to 4.1.4

I am running Unity 4.1.4 on a Windows 7 64 bit computer. Since loading 4.1.4, whenever I click on a JS file, it opens two empty windows, on large and the other smaller. Both are dead. When I click the close button on either window, both close. I tried to close only one through the Task Manager, but, again, both close.

I tried uninstalling and reinstalling Unity but that has not solved the problem.

Thanks in advance for your help.