Hi, I've had issues with Support Assist having failed after my PC was 1 year old.  As I didn't want to wipe the whole computer to re-install everything, I had been manually reviewing and adding critical updates based on my Service Tag.   For the last 6 months these have failed to install - the error message is:

"this application is supported on supported systems only.  If you have received this message in error, please contact technical support"