Determine a Computer is Infected

Owned by Moffat, Ethan
Last updated: Jul 21, 2023 by Hernandez, Jess

How to Tell?

Any abnormal behavior of a computer system may be an indication of virus activity. In the extreme, a computer will no longer boot up or will freeze in the process of booting. In some cases, the computer may suddenly freeze during normal use or run slow for unexplainable reasons. If in doubt, check it out.

What to Do?

If you suspect that you have been hit by a virus, the following steps may help you recover and get back on track:

  1. Check the Windows Security Center to verify that system updates, antivirus software, firewall, and anti-spyware applications are running and up-to-date. See System Health Requirements for more information on verifying these settings.
  2. Isolate the system by unplugging it from the network. Collect any and all removable media that has been recently used on this system as it may be infected as well.
  3. Run antivirus scans on the system to verify that there is truly a virus infecting the computer in question. Check that anti-virus data is current; if it is not, download the most up-to-date software on clean removable media from a clean networked computer.
  4. Contact the CIS Helpdesk to see if any known viruses are circulating and alert them of your situation.

What to do if Infection is Confirmed

  1. Determine where the virus may have come from; notify the person or site who sent it to you.
  2. If on-campus, notify CIS that you have confirmed or strongly suspect malware on your computer. Back up essential data onto a separate media storage device.
  3. Eradicate the virus from your system. CIS provides a virus removal service free of charge for Faculty, Staff, and Student computers.
  4. Restore or rebuild the system, applications, and personal files.

A number of web sites offer helpful virus alerts and diagnostic/eradication steps. The technical detail is beyond the scope of this article. The first place to go is to the web site of your antivirus software manufacturer.

When dealing with viruses, It is better to be safe than sorry. People sometimes ignore early indicators that something is wrong and end up losing important data and compromising other networked systems.