SweetFX is the graphics shader and configurator that has been making the rounds lately. It can enhance the appearance of games like Aces High. The most recent NVidia driver update broke something and required either a reinstall of SweetFX, or completely removing it and AH and starting over. The precise message the OP posted is the result of the Nvidia update on top of at least some SweetFX installs, although there are other reasons it might show up. Either way, the timing made me suspect that it is the update that might have caused the problem.
Sorry for the interruption.