CompTIA A+ Certification All-in-One Exam Guide

might get automated replies from unknown sent e-mail that you know you
didn’t send. Most of these issues are easily caught by a regular anti-malware
scan, so as long as you remain vigilant, you’ll be okay.
EXAM TIP While it’s not necessarily a malware attack, watch out for
hijacked e-mail accounts belonging either to you or to someone you know.
Hackers can hit both e-mail clients and Webmail users. If you start receiving
some fishy (or phishy) e-mail messages, change your Webmail user name
and password and scan your PC for malware.
Some malware even fights back, defending itself from your many attempts
to remove it. If your Windows Update feature stops working, preventing you
from patching your PC, you’ve got malware. (CompTIA speak: OS updates
failure.) If other tools and utilities throw up an “Access Denied” road block,
you’ve got malware. If you lose all Internet connectivity, either the malware
is stopping you or the process of removing the malware broke your
connection. (CompTIA calls these Internet connectivity issues, which seems
very polite.) In this case, you might need to reconfigure your Internet
connection: reinstall your NIC and its drivers, reboot your router, and so on.
Even your browser and anti-malware applications can turn against you. If
you type in one Web address and end up at a different site than you
anticipated, a malware infection might have overwritten your hosts file. The
hosts file overrules any DNS settings and can redirect your browser to
whatever site the malware adds to the file. Most browser redirections point
you to phishing scams or Web sites full of free downloads (that are, of
course, covered in even more malware). In fact, some free anti-malware
applications are actually malware—what techs call rogue anti-malware
programs. You can avoid these rogue applications by sticking to the
recommended lists of anti-malware software found online at reputable tech
sites, like Ars Technica, Tom’s Hardware, Anandtech, and others.