I like both Jetico and Kerio 2.1.5 firewalls because they are free and very resource-friendly compared to many other firewalls. However, I have problems with both. Jetico 220.127.116.11 bug: it works fine initially and then gets confused about process identification *after* certain security events. For example, with Jetico active, I run Opera 8.5 which initially works fine. I then open a command prompt. I then run my own program that generates a security alert (modifying one of ANY another process, totally unrelated to Opera) and tell Jetico allow it. After this, Jetico issues a network alert everytime Opera tries to access a website, but Jetico identifies Opera as "CMD.EXE". Jetico bug #2: I already replaced Jetico with Kerio 2.1.5 so I cannot confirm it but I think Jetico's firewall doesn't differentiate between different programs launched from the command prompt. Note that in the above example, Opera was launched normally (start menu) so this is a separate issue. Kerio 2.1.5 bug (Firewall Engine Version: 2.1.5 and Driver Version: 3.0.0): try this simple test: 1. in command prompt, try "ping www.freebsd.org" and you'll correctly see: "Pinging www.freebsd.org [18.104.22.168] with 32 bytes of data: Reply from 22.214.171.124: bytes=32 time=67ms TTL=48" ... 2. click "Stop all traffic" from the kerio tray icon menu 3. in command prompt, try "ping -l 5000 www.freebsd.org" and you'll see that network activity isn't blocked: "Pinging www.freebsd.org [126.96.36.199] with 5000 bytes of data: Reply from 188.8.131.52: bytes=5000 time=222ms TTL=48" ... So basically, Kerio 2.1.5 seems incapable of preventing a local program requesting and then receiving response from a remote machine on the internet even while Kerio's "Stop all traffic" option is selected. Are there there any solid alternatives to these 2 firewalls? I just want something very resource-friendly to work well on Windows 2000 sp4. I want the firewall to do its core functionality well instead of bundling a bunch of non-firewall features that I can get from other products.