We were able to fix it...
The problem ended up being a tool bar on the left hand of the screen. He moved the tool bar to the top and all the sudden his minimize and maximize are working correctly again.
Could you go into more detail on your fix here please as I'm not sure what you mean/what you did to clear the problem. Which toolbar etc?
We're having the same problem on a regular basis and would love a fix.
Misty hasn't logged in since February and she was probably running SW12 or older, but her solution is worth trying.
If you have toolbars on the left, try moving them one by one and testing the min/max state.