When you use Windows Task Manager to kill a process, you may receive the message “Access Denied”. It is strange because you are on a privileged account. So how to overcome this issue?
To kill a process which gives access denied, you can use Process Hacker. It is a free, powerful, multi-purpose tool that helps you monitor system resources, debug software and detect malware.
You just run Process Hacker, right click on the process you want to kill and choose Terminate. There are both installation and portable versions for your choice.