The best way to determine if your computer's (or router's) firewall is working and optimized is to effectively try to penetrate it. Browser-based utility ShieldsUP! tests your firewall for ...

If you've recently added a new firewall and aren't sure if it's running properly — or just want to run a spot check on your existing firewall — here's how to make sure your firewall is working.

A port test service like PortTest scans your firewall to make sure your computer is invisible. If it can see you, so can the hackers. Click here to test your computer’s firewall.

3. Test your firewall One of the most fundamental security setups is a firewall. Windows and Mac have decent firewalls built in, and many third-party security programs include them.

So how do you find out whether your firewall is solid? Luckily, there is a quick and easy way to test it. Tap or click here to test your firewall and make sure it’s working. Uber Spies ...

If you're troubleshooting intermittent network connectivity, spyware could be the culprit. Jonathan Yarden tells you how to check your firewall for spyware infection.

Test your firewall. One of the most fundamental security setups is a firewall. Windows and Mac have decent firewall built in, and many third-party security programs include them.

If you have a PC running Windows XP Service Pack 2, the firewall program is turned on by default. You can check your settings in the Control Panel area of the Windows Start menu.

If you're troubleshooting intermittent network connectivity, spyware could be the culprit. Jonathan Yarden tells you how to check your firewall for spyware infection.