Vista - Messenger problems

Hi All,
I really hope you can help me with this, cos it's getting very frustrating.
I'm having problems with Live Messenger 9 (14.0.8064.206).
I have a Windows Vista 32 Ultimate SP1 and a brand new PC (i7-4GBDDR3-DX58SO-280GTX), the problems are that messenger keeps crashing, it signs in normally and seems working as usual but then as I try to open the main window, it doesn't respond, or when I'm away from the PC and return, I find it not responding and I have to terminate its process from the task manager and re launch it again. It happens very often.
The second problem is that I cannot use my webcam and none of my contacts can use his webcam with me. Whenever I use my webcam with a contact, I can see the image for a couple of seconds and then it says "your webcam session has ended" and the contact doesn't see anything.
This also happens when a contact tries to use his webcam with me.
I uninstalled messenger and cleaned the registry and reinstalled to no avail. I also used another webcam with no success.
I have no add-ons for messenger whatsoever and everything is up to date.
Is there any way to find out what's causing this?
Thanks All.