Last mont I had some problems with meshing. It turned out to be the panda virusscanner. Yesterday I did the service pack of inventor 2013. And agen no meshing. (even without panda virus scanner)
I am realy sick of these problems!
We have a similar issue reported through our product support channel, and Development has determined the cause.
I'm not sure if this is the same reason, that the meshing is not working on your machine, but it may be worth a try:
It could be that UAC control on your system is preventing these environment variables to be set temporarily by Inventor.
I hope this helps, -Hugh
I created the system variables that you listed. Inventor is still failing to mesh. Please let me know if you can think of anything else to try.