Meanwhile, could you please try restarting your machine once, just to ensure an in memory older adb is not in use.
So, was a newer driver supposed to be installed by downloading the latest SDK? What driver should be installed?
I simply opened Windows 7 Device Manager and did an 'Update Driver' and 'Search Automatically' and it found an update and installed it, asked me to reboot and next reboot it worked.
I've tried to update the driver automatically and it simply says it's up to date. I've also tried to use the drivers shipped with Flash CC and Windows didn't recognize them as valid drivers at all.
What driver did you initially install?
-A