I got this error when trying to run MATLAB 6 R12.
“Failure Loading Desktop Class”
The first result in Google didn’t help. But Solution 1-1881O did.
I’m running Windows XP on a Dell Dimension 4600 with a 2.4 GHz Pentium 4. With a similar (P4-based) setup, you may get the same error. To fix it, simply download and run this patch: JREpatch.exe.
Make sure MATLAB is closed when you run it. The first time I did, I was running MATLAB (although it wasn’t working) - and some files couldn’t be overwritten. After running the patch, MATLAB worked like a charm.

Worked !!
At first it didnt as I hadnt changed the classpath in the MATLAB_JAVA variable in the system enviornment.
It works fine now.Thanks !