Context Menu Can't be opened cause searching.

I've had the same thing happen a few times but I closed my thread off because it didn't reoccur after I posted about it.

The only thing I've done since then is update my gfx card drivers, not sure if that was the fix or I've just been lucky to not run into the bug since then

This is a known bug from live, and it likely has several triggers (look for "hands lock" in the official EFT patch notes). I've experienced this quite a few times (mostly on 1.0.0 and 1.1.0, and much less frequently on versions since), and I "solved" it by paying close attention to what I was doing in-game so that I could narrow down when the bug kicked in, and what I had done that might have triggered it.

My best advice is to pay close attention to what you do while looting containers/corpses, and then open your own inventory after you back out of each container/corpse to see if you can still right click things in your inventory. If you can still right click, then you haven't triggered the bug and you can move on. If it won't let you right click on things in your inventory, then something you did since you opened that last container/corpse caused the hand locking bug.

In my experience, it seems to be caused by exiting the inventory/looting interface while a magazine load/unload action is still in process--once I noticed this, and I made a conscious effort to stop exiting out of the inventory/looting menu without finishing or manually stopping magazine loading/unloading, I went from having my hands lock every 2-4 raids, to having them lock maybe every 20-40 raids.

I'll note also that my hands didn't always lock to the same degree--Sometimes it would just lock me out of the right click menu without preventing me from searching things. Sometimes it would lock me out of searching rigs/pockets/backpacks of corpses, but not static containers. Sometimes it would glitch out on one or two containers and then start letting me search things again but with my hands still partially locked. Very rarely, it would lock up my hands so completely that it wouldn't let me fire my gun.

Also, a helpful bit of advice if it happens again and you need to eat/drink/med: Even if you can't right click on them in your inventory, you can often still use them by tying them to a hotkey, and then using that hotkey.