Thanks for responding Michel. Is ZoneAlarm a good option? I don't want to increase cost at this moment. Also will those on my LAN (W98 machines) be able to access the Internet. Actually I don't want them to at this moment.

>>Yesterday I changed from a Dial-Up ISP to a WAN/cable based ISP. I have 2 LAN cards, 1 for my local LAN, 1 for the ISP.
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>>Now what is happening is that all the machines including mine are onto this network. I am worried that my machine is also available for access. I use W2KPro and have given access (limited to a given login) to a few folders for my actual LAN users.
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>>How vulnerable is my machine for unauthorized accesses?
>>What security can I use or what configuration changes to W2K is required?
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>Whatever is pingable becomes visible on the Internet. If you really want to keep that setup, a firewall is always the best investment you could do for security. I used to have a setup like that in one of my first setup. I didn't like it because of that. As soon as you have more than one PC connected to the Internet and if you are worrying about some PC that are connected but don't need access to the Internet, a good protection such as a firewall would be a good investment to make sure that those ones would be completely not viewable from the outside. IAC, the base rule is always to have such a setup, even for one PC. :)