In general you should never touch files in the Matlab installation folder.
In this case the solution is simple: you didn't create a finish.m file that saves a mat file. Now you try to read that non-existent mat file, which fails. You should make sure such a mat file exists, preferably using a relative path (e.g. with mfilename('fullpath') ) and compose different parts with the fullfile function.
In other words, you should change the example to what you actually want to happen.