Well, hey. After a month with no problems, it's happening again. Parallels Desktop 9.0.24237 just greyscreened. I just submitted Problem Report ID 47125589.
And take a look at this:
Note that I have four VMs running (all with updated Parallels Tools, except for the tails VM, which has no PT installed at all). All of them are in fullscreen mode, and on the secondary monitor, but only three of them actually appear in Mission Control. When I sent the four VMs to the secondary monitor, and then they went grey, all hell broke loose with my virtual screens. The Parallels VM list jumped around between various screens, screens jumped from one monitor to the other and rearranged themselves, and obviously Parallels has lost track of one VM's screen altogether (actually, I figured out that it "stacked" the WinXP and tails VMs on top of each other--in fullscreen mode). I don't know what's happening, but the problem just got significantly worse.
This all reinforces my theory that Parallels Desktop has a fundamental conflict with the virtual display system in Mavericks. It's still not fixed, y'all.
Last edited: Jul 17, 2014