Error message when trying to load AVS script

[MaxPlanck]

I receive the following error message when trying to load an AVS script

ConvertToRGB: 24-Bit RGB and Rec.709 support require MMX and horizontal width a multiple of 4.

[Guest]

Crop your video's width to a multiple of 4 before calling ConvertToRGB(). If you need help doing that, post your entire script.