It is showing invalid MEX file error, when using sca code

I am new psychtoolbox user. I have installed in MATLAB. It is showing error (invalid MEX file) when i am using sca code. What should i do?

First you should read the posting guidelines on how to ask questions efficiently, so anybody could understand your problem. Also make sure to reread the download/installation instructions and system requirements first and make sure you followed them to the point.