For clients with Windows XP systems, I generally recommend enabling the Windows firewall and disabling any third-party firewall software (this would include your Norton firewall). The main argument against this is that Windows firewall is what they call a "stateful inspection" firewall, which is not smart enough to know that the worm you just activated by opening the attachment in the e-mail is filling your system full of spyware, etc. My argument for this strategy is threefold:

1. Adding another firewall to your system needlessly complicates the system and uses additional resources.
2. Keeping your antivirus software updated will allow it to catch these types of threats
- and -
3. Most of my clients know to NEVER OPEN unknown e-mail attachments and to BE VERY CAREFUL opening e-mail attachments sent by friends, family, etc. :-) They know this because I lecture them about it every chance I get... :-)


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