Windows Command Processor Notification Virus

I have a laptop, which is running under Windows 7. The problem on my PC started after I allowed Windows Command Processor Notification virus to make changes on my computer. I thought that it was a real Windows pop-up. The message appeared like this:

User Account Control
Do you want to allow the following program to make changes to this computer?
Program name: Windows Command Processor
Verified publisher: Microsoft Windows
Program location: “C:\Windows\SysWOW64\cmd.exe” /C “C:Users\Serge\AppData\Local\Temp\lkjitbhcythsqijd.exe”

I need someone to help me remove Windows Command Processor Notification virus from my computer. Since the infection, I feel that the PC is getting slower every day. It seldom crashes so I have to reboot just to make it useful once again.

Serge