Cannot play game due to gfx card error

[Unmannedperson]

So every time I open Trainz 2010 on my computer using Steam (I only have a steam copy, not hard version, if it matters), I get an error message reading:

NVIDIA display drivers files from different (incompatible)
versions of the driver have been detected.

NVIDIA OpenGL acceleration is disabled in order to
maintain system stability

To resolve this problem, update the NVIDIA display driver.
The latest driver is avalible at http://www.nvidia.com.

After closing this message, the menu opens with the "play/options/extras/etc" buttons. If I click "play", a dialog box opens checking all kinds of assets. When it gets to the "Checking failed assets" section, the error message above comes back and when I close it, the game crashes.

Extra info:
-I have opened options and changed "OpenGL" to "DirectX", to no effect.
-I have tried restarting steam, Trainz 2010, and my computer.
-I have gone onto the website and updated the drivers to the most recent ones.
-My graphics cards are dual MSI N250GTS Twin-Frozr s
-I have dl'd the game onto my laptop and it works just fine, albeit painfully slowly.

Any help is greatly appreciated!