Why My Firewall Was Disabled

Two things will keep you from using your firewall: The first is a faulty installation, which you can often fix quickly. The second is more worrisome. Spyware and other malware can turn off or completely kill your firewall as part of its plan to hijack your system.

If you think your firewall did not install properly, uninstall and reinstall it using the directions that came in your software’s users guide. On the other hand, if your firewall installed correctly and worked fine until you clicked a suspicious Web site or opened a specious email, use a spyware/adware detector to clean your system. Norton, McAfee, Zone Labs, and LavaSoft all make wellknown programs that can remove most but not all malware from your system.

You can also contact your firewall vendor to see if it offers a fix. For instance, McAfee’s firewalls can be attacked by spyware that very subtly edits the Windows Registry to disable it. It alters the following Registry key:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon\Notify\SensLogn

to read as follows:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon_disable\Notify\SensLogn

In the second key, there is an extra word disable. Rather than fix it yourself, it’s better to contact your support team because even the smallest change to the Registry can result in disastrous effects.

Once you’ve run a spyware tool or a utility from your firewall vendor, you may have to reinstall your firewall because malware can leave it so damaged that you need a fresh copy. If the problem still persists after all these steps, contact your firewall vendor again to seek help.