When I enter full screen mode with Parallels 11 & Windows 10 on a Macbook Pro - El Capitan, I cannot exit full screen. I have to shut down Windows 10 completely. Also, some programs in Windows 10 (in Parallels 11) cannot be resized.
Please change the VM settings like described below and check the issue: 1. Open VM configurations 2. Choose Options -> Full screen -> click "active Screen corners" 3. move your mouse on the right corner and exit from the Full screen.