I had Microsoft Security Essentials set up on this laptop before giving it to my daughter, but appears to have been disabled along with the firewall and system restore. I also noticed that when using the admin account, a couple Chrome extensions automatically tried to add themselves, so this or another virus might be trying to do something to the new admin account. One of the extensions was called wajam. My daughter chose to use IE instead of Chrome, so that was probably the browser in used when the laptop was infected.