Hello and welcome, I see you posted this in VIsta forum (and you are bnew here).. I am moving this to the Am I Infected
forum as you most likely are.
Please do this first.. It may also fix the Task Manager issue.
I suspect and Internet Security 2010 or similar here.
As this infection deletes a core executable of Malwarebytes' we will need to download a new copy of it and put it in the C:\ tc... so please follow our Removal Guide here http://www.bleepingcomputer.com/virus-remo...t-security-2010
You will move to the Automated Removal Instructions for Internet Security 2010 using Malwarebytes' Anti-Malware:
After you completed that post your scan log here,let me know how things are.
The log is automatically saved and can be viewed by clicking the Logs
tab in MBAM.
Copy and paste the contents of that report in your next reply. Be sure to post the complete log to include the top portion which shows MBAM's database version and your operating system.