John, we’re going to need a little bit more info than that. What steps are you working through and where’s it going wrong? Are you getting an error message? What settings are you using in the extrude filter dialog? Basically, what are you expecting, what are you doing and what are you getting?
P.S. There are some good instructions for using the extrude filter in the online help- might be worth having a read of that in case there’s just a setting wrong or something.
Extrude won’t be available if your image is in LAB color mode.
Also, Extrude is quite processor intensive.
With a large image and a small tile size, it can take quite awhile.
And finally, if you are used to extrude from a 3D program, you will be disappointed to learn that PS extrude filter is in no way related.