That is most certainly an odd error message. You mentioned that you assumed the drivers updated, though they may have not. I'd still try to update though this really looks like a different type of error than drivers.
It might be a long shot, but I'd power down the system, open the case and ensure the video card is seated properly, if you are even able to as this sounds like a laptop. Seems very "hardware like" in that error message though I did a quick search and it has been seen before and may actually still point to drivers.
I have this problem too. they can do die & as most graphic cards in your computer are part of motherboard therefore not removable, you try to get it fixed or get a new PC
Have you tried a uninstall and reinstall? Also, make sure your NVIDIA card is free of dust.
Any luck on this? Did you try and update the drivers to be sure?
Thanks for your input everyone- I did a full re-install of AE and updated the drivers for NVIDIA- things I should have probably done before starting the thread. But I'm happy it seems to have sorted the problem.
The only difference is that when AE starts it prompts me that there are an import and an export plug in missing, but I am able to export directly from After Effects or use the media encoder.
Thanks again, I am much calmer!