A friend has Win XP and he keeps getting reminders to download and install security updates. Are these really necessary if he runs a firewall (in his case Zone Alarm) and has anti-virus software (AVG) which he keeps updated?

Thanks

YES most likely.

If they are critical updates an antivirus program or a firewall may not protect you.

Highly recommended that you install all all the criticall updates that you need for your system.

I personally don't install all non criticall
updates and DirectX9.

But many others should be installed.
A firewall and antivirus are not enough.

All on this forum would agree wholeheartedly.

NO, most definatly not! Do not install any updates. They were designed by Bill Gates and the government to keep the white man down. They use these updates to take our jobs, our land, and our women.
This post was as rediculous as the question that was asked--OF COURSE you should install the critical updates!

What are the three cardinal points in any security best practice list?
1. Run an resident Antivirus.
2. Run a resident firewall.
3. Install all critical updates for your OS.

Critical updates patch the code of your OS, thus eliminating a flaw. If you rely on your AV, you must rely on any updated definitions to catch the latest exploitation of that flaw which you have not fixed.
Regards,
John