I've run into this particular error before in another sim... Uninstall and re-install your video card drivers... maybe even re-seat your video card. At least it worked for me... what was happening was that different models called on different parts of the GPU to render... in my case it was the shadow cast on a wing when I raised flaps in G3... Any model with flaps would crash the program when it tried to load the collision mesh and render the flaps (and what was under them).
If you're using an ATI video card, be sure to download their driver un-installer and use it... I assume nVidia has a similar tool?
-Case
ORIGINAL: RC-Captain
For the problem you're having, can you try resetting the options, and let me know if that fixes it? Here's the approach:
I set the messafges according to what you sugested and this is the error message I receive when trying to fly the voyager 50 w/training gear.
The instruction at Ox004a07e6 referenced memory at '0x000000000' The memory could not be read.
I deleted and reloaded the program twice already .