Backup on shutdown doesnt work. HELP! PLZ!

I tried to configurate Acronis True Image Home 2010, that its going to do the backup on shutdown. But it doesnt work. I also wrote a shutdown-batch which should shutdown the notebook after the backup's done. I added it to acronis "Post commands" in the "Backup option" but it didnt work!

System: Windows XP Professional 32-Bit notebook.

Now to my question: How do i get the "Backup on shutdown" workin?

If you ned some more informations, then plz ask.

THANKS IN ADVANCE!