How to Achieve Conficker Fast Removal Safely

Conficker Fast Removal is a historical classification of specialized anti-malware tools released by major cybersecurity firms in 2009 to quickly eradicate the widespread Conficker (Downadup/Kido) computer worm.

First detected in late 2008, the Conficker worm targeted older Microsoft Windows operating systems by exploiting a vulnerability in the Server service (MS08-067) and spreading through weak passwords and shared network folders. At its peak, it infected millions of computers worldwide. The Problem with Conficker

The worm was notoriously difficult to remove because it employed active countermeasures to protect itself:

Virus alert about the Win32/Conficker worm – Microsoft Support