I'll pan MS Defender since it allows spyware such as ALEXA a pass into the system. But I'll move on to what I'm using without any issues.
1. Free AVG AntiVirus.
2. A browser other than IE or any that is IE based.
- This sidesteps the issues with IE so I don't have to deal with it.
3. For spyware I may scan with the microscanner from http://www.ewido.net/en/onlinescan/ but nothing nasty is found due to the non-IE use.
Since I have a fine backup system I am currently testing with the stock firewall and so far so good except for those sites that Microsoft deems to be fine but I disagree (Alexa for example.)
Let me close that as long as Microsoft give a pass to ANY spyware such as Alexa or others they own then they are not a viable vendor for antivirus or other protection software.
To answer your question, for me the Vista firewall is fair but I'll move to Zone Alarm or another when my testing time is up. The reason is simple. Microsoft has a less than airtight solution.
Bob
My new laptop is around 6 times as powerful as my former one, but thanks to Vista, it runs about the same speed. I'm not eager to slow it down with protective software, so I don't want to load anything unnecessary.
I hear that Vista has a decent firewall, if you can turn on the "outbound protection".
- Is it really good, or should I disable it and download ZoneAlarm?
Also, there's that nuisance of a program that pops up every time you try to make a change; does that replace Spybot?
And Microsoft Defender: is it any good, or do I need Ad-Aware, AVG Anti-spyware, etc?
And so on.
On my last computer I had AVG Anti-virus, rootkit, anti-spyware. I also had Ad-aware, Zonealarm, Spybot, and Spyware Doctor. How much of that do I need for Vista?

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