Go to http://www.dslreports.com/forum/tweaks and read some of the posts regarding your problem you did not state which version you are using
I have a DSL connection through a modem with a built in hardware firewall. I installed the Zone Alarm firewall to give me a "in and out" protection which the hardware firewall does not provide. I find that as the day progresses the ZoneAlarm and the hardware firewall seem to clash. What I mean is that after I boot up the computer in the morning the connection to the internet works flawlessly, but as the day progresses late in the afternoon I cannot get through the firewall and neither the Outlook Express nor the Internet Explorer can find the server till I turn the Zone Alarm off. First I thought that it may be just a coincidence, but it is happening regularly that I am now convinced that it is a clash between the hardware and the software firewall.
Surprisingly, when I operated with these two firewalls when my operating system was Win 98SE I did not experience any access hang ups to the server. I only started getting this problem recemtly after I upgraded from Win98SE to WinXP Professional version.
I checked to make sure that the Microsoft's firewall built in the WinXP was turned off. I am told that this latter is not a very effective firewall.
Would appreciate if anybody has had a similar experience and has found a solution.
My system is a Dell 4100 with a P-lll 800 Mhz CPU, 256 MB RAM, 2 Hard drives a 80GB and a 20 GB running Win XP Pro edition

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