Help! My computer is refusing to download any files.

[Baron Munchausen]

Contemporary viruses and trojans are actually smart enough to hide themselves from the built-in task list. You need something 'non-standard' to check for them that way. Unfortunately, the problem being discussed is inability to download so I don't know how you'd acquire something like Powertoys or Kerneltoys with some extra Windows snooping tools (from the MS Programmers themselves, no less!) with that problem in the way.