The issue is that one needs to put the mouse at the top pixel-row of the main display and not the top pixel-row of the highest display. When the main display is not the highest display, this is next to impossible. I would request Parallels to have the menu bar unhide in a more user-friendly way for those using multiple monitors.
Hi JulianP4, You can press Ctrl+Alt and then the area that triggers menu appearance will become big enough. The delay and one pixel area was implemented to help users close/minimize their Windows apps without triggering the Mac menu. I understand it is not usable if you have a monitor located above.
Hi Alev Ctrl+Alt didn't work for me; it just tried to do something weird within Windows not Mac. I found the solution, and that is to be sure I place the non-full Windows10 window on the monitor I wish to be the main one before I hit the green button. Windows then gets arranged nicely across all monitors in full mode where the top pixel row is now on the original monitor I selected. So long as this monitor stops at the top and does not continue to a higher monitor, this results in a perfect ability to unhide the menu. Thanks for your input, Julian