Dreaded GMAX right-click issue

I know that there have been various issues both here and on other forums regarding quad menu issues, but none of the suggestions I've come across fix this for me. A few days ago I lost most of my right-click-ability. I'm aware that there are driver-related issues, but this is different. I'm not aware of any changes lately which would cause this (within GMAX, video driver, Windows update etc), and I've even restored GMAX entirely from a backup, just to make sure I hadn't inadvertently changed anything.
My quad menu just doesn't appear at all, neither does right-clicking the viewport labels. It isn't a mouse issue, as I can still right-click outside the viewports.
I can live with this, but it is awkward. I wonder if there's any way to bring up the Quad menu another way?
Otherwise this might be nature's way of telling me to move on from GMAX.
Ok, I've just this minute finished a Windows update, which fixed this! I suspect that a previous update might have caused it. I'm very glad it's fixed, but I'm very aware that GMAX isn't going to last forever.
I've had similar problems from time to time with no consistent way to resolve them. Sometimes restarting Gmax or a reboot takes care of it, sometimes a video driver update was necessary to sort it out. I'd also say be sure to avoid the DirectX Gmax driver, only use OpenGL or the Heidi driver. DirectX support seems to be getting more broken over time (at least that's how it's been for me).