I found myself in an odd predicament earlier when I couldn’t get the IIS Manager on one of our Windows Server 2008 R2 boxes to open. When I tried to open it, the IIS icon showed in the taskbar but clicking on it had no effect. I tried just about everything to restore it, even restarting the box to no avail.
The fix for me was to run
Inetmgr.exe /reset which resets your IIS preferences, including window size and placement.