Cleaning an Infected Computer Guide

The only way to be 100% sure that a computer is not infected after an infestation is to re-install the operating system. However, for less insidious infections, cleanup may be possible. The following steps provide a general course of action for addressing minor infections.

 

  1. From a separate computer, change all passwords you have used on the infected machine (e.g., e-mail, social media, bank). Also change the password for any account that uses the same password as an account you have accessed from the infected machine to prevent potential break-in to those accounts.
  2. If the infection originated from an e-mail, use a Web based tool to delete the offending message (e.g., Faculty: http://email.sfsu.edu, Students: http://live.sfsu.edu).
  3. Windows: Restart the computer and boot into Safe Mode with Networking (hold the F8 key during startup until the startup menu appears).
  4. Download and install all of the anti-malware applications recommended for your operating system on the Recommended Anti-Malware Programs page.
  5. Run a scan using each of the anti-malware tools.
  6. Windows: Restart your computer normally and re-run all of the scans.
  7. Verify that your Anti-Virus software program and definitions are up to date. Current students, faculty, and staff are eligible for a free copy of McAfee VirusScan.

 

If you would like help cleaning an infected machine or, in the case of severe infections, reinstalling the OS, assistance is available to current students, faculty, and staff on a first-come-first-served basis at the ITS Help Desk (ADM 110). Please plan to spend several hours on-site as machines not owned by the university may not be left unattended. Please bring your own disks/media for operating system re-installations.