Removing pupil texture

I’ve been working on a zombie model pack, and I need to remove the pupil texture from the eye without causing the purple-and-black checkerboard error. Does anyone know how I would do this? Thanks in advance for any help.

Edit the eye material vmt?

get the eye’s vmt and search for $iris just // it out and it should work.

I’ve tried removing the iris line from the VMT, but I’ve come up with this:

http://img294.imageshack.us/img294/6237/gmconstruct0001l.jpg

The pink texture also moves when you use the eyeposer.