Acronis 2009 not working

This is My brothers old desktop Fujitsu Siemens. It bears a Vista sticker but seems to have XP on it. He bought this in a store in 2008.
I am the one who installs all pc's in the family and instructed my brother to buy Acronis. He did that and I find the images I made when preparing his pc (removing northon/partitioning etc)
I remember going back to him a few months later to teach him to make acronis images but was asked for a password and he didn't remember it and was going to look for it later. So we stopped trying.
Now he bought a Dell laptop that I prepared again and this time I ordered and payed for the acronis and have the registration numbers stored away safely.
Now he wants me to prepare his old desktop to give it to his daughter.
I tried making acronis images but did not succeed. Here in this forum I found a thread where it was explained that you need to use the pc password. That did not succeed either. Another solution is to reïnstall Acronis. But then I will need his registration.
How can I get it?
I see that my brother downloaded the Acronis true image setup file on 5/12/2008 18:31 this would probably be on his actual mail address (don't like divulging that here - but can send it if you need it.)

Also - I now discover the pc with Vista sticker in fact has XP on it. As Windows stopped supporting XP I would like to reïnstall Vista on it. The Vista number is on the machine so that should work. But again - I will need to reïnstall Acronis
Would the registration be somewher in the registry????