Empty RowNames and ColNames?

http://www.mathworks.com/products/bioinfo/examples.html?file=/products/demos/shipping/bioinfo/cnsgeneexpdemo.html

I’ve been going through this tutorial using my own CEL Affymetrix files for Arabidopsis. After loading the MAT file with the three DataMatrix objects, using the get command, I am only able to pull up empty RowNames and ColNames. Has anyone ever experienced this and know how to fix it?