Brightness control is broken, all methods tried

Hi,
I have a Sony VAIO CW Core i3 laptop which is running Windows 7 Professional Service Pack 1 64-bit. I cannot change the brightness anymore (probably since the SP1 update).
I get this: http://puu.sh/1nWX It maxes out at one bar. Furthermore, the brightness control is now gone from Windows Mobility Center: http://puu.sh/1nYJ

My video card is nVidia GeForce 310M. I've already tried methods mentioned in other forums as well as Sony Support, such as installing and reinstalling Sony Shared Library and Sony Notebook Utilities, as well as uninstalling all nVidia drivers and reinstalling them.

I've tried installing the newest nVidia driver from the nVidia website, but that failed and told me that I don't have compatible hardware (which is crap because I chose the right model..)

What else can I do? Is this because of Service Pack 1? Is there anything else I could try before trying to roll back the service pack?

Thanks.

Ok, looks like I fixed it.. seems that installing the video driver in TeamViewer breaks the native functionality. Uninstalled it from the advanced options, and brightness controls are back!

Hey,

I've been having the precise same problem as you for many weeks now and last week I restored to a fresh install because the sun bed effect at night time was bugging me so much :P Anyway, a few days back the problem returned and as you I tried many many solutions, non of which worked. I also have recently installed SP1 but I knew that wasn't the reason. Of course I use team-viewer as well and their screen monitor driver which is bugged for at display of blank screen overrides the inbuilt native drivers.

Thank you SO SO SO much for your help ^^ saved me an angry trip to Packard Bell xD