I too have been having the issue of scheduled scans and updates not running now for a few months. I have followed the instructions as posted here: I've done clean removals (twice) with varying results. The first time the scheduled processes ran for a few feeks then stopped. This past time everything ran automatically once then stopped. I can manually run updates and scans with no problem.
Attached is the CHeckResults.txt file from the mbam-check program downloaded on 9/14/2013.
Any help you may afford would be appreciated, and let me know if I can supply you with any additional information.
Grand Forks ND