How to Scan and Repair an Infected Computer From Outside Windows: "If a Windows system is badly infected with malware, running an antivirus from inside Windows often won’t help. You can more easily find and purge malware by scanning from outside Windows.
Malware can hide itself on an infected system, avoiding detection. Other malware may attempt to battle the antivirus software, preventing it from properly installing or scanning. This is why it’s important to catch malware before it infects you"
'via Blog this'