Malware can take many forms but one of the most common is a malicious process running on your system. These processes run the background along with other essential Windows processes and can do anything from infect your system with a virus to open your PC to attack from trojans. Windows Task Manager can sometimes help you kill them but often, they’re hidden or downright impossible to stop.
One solution I’ve always found effective in these cases is Process Killer which basically acts as a glorified version of Windows Task Manager. It’s more effective however in that it shows every single process running and is devastatingly powerful at stopping them. The downside is that you have to be VERY careful when using it as you can kill an essential process that can crash Windows.
For those who are intimidated by Process Killer, I recommend Magic Utilities which includes an idiot proof process killer that’s pretty powerful but much safer. What I like about this is that if you’ve killed a process but it’s simply frozen the program on your screen, you can kill the program too and remove it from your desktop.