Home Networking Problem

I have three computers in a network at my house connected to a linksys 4 port switch/router. Everything had been working perfectly for a long time. Then my main computer stopped working with some aspects of the network. Everything from an HTTP server seems to work fine, but when I try to connect to anything else something stops the connection.

Here's the parts that sort of has me stumped. The other two computers on the network do everything perfectly, ruling out the router as the problem, and even so, I reset it, having the same problem. I also have the same problem when connected directly to the cable modem.

A few days after the problem started, my mobo fried, so I had to replace it. The problem didn't go away, but I couldn't connect to the microsft activation server for my new mobo, so I had to call them and get my number. I reinstalled the card and my TCP/IP related things several times, but I belive I am missing something, or else all the settings would fall back to default and things would be just fine, they aren't. I have all firewall related things on the machine turned off, and uninstalled if possible.

I am able to ping the problem machine normally through any other computer on the network, but cannot ping from the problem machine.

Please help. If you need ANY information I didn't provide please ask.

Do you have any firewalls running?

None at all, but the computers that DO work on the network are running Zonealarm. One thing I found out is that I can do a port scan on the other network computers, it appears to work, but when I do a ping on them I get "PING: transmit failed, error code 65". I have doubts that the port scanner is actually working properly because it indicates all ports are open on the computers with the firewalls installed.

Have you tried switching out the nic in that computer? I used to have one that would short out the whole system. That might have explained the mobo failure as well. Just a thought.

Try a cable from one of the other machines. Try your cable on one of the other machines. If the problem goes away or moves, buy new cables.

Are you sure your protocol is configured correctly?

I have swapped network cards and it didn't seem to work, but there's no reason I can't do it again. I pretty much have the problem narrowed down to me screwing up the configuration somehow. How do I completely uninstall all network cards and protocols in WinXP? I had done this hundreds of times on win98, but WinXP seems to be keeping some part of the configuration and reloading it as soon as I put the card back in. I need something step-by-step in unistalling everything netowrk related. Microsoft's "ease of use" strikes again.

Right click your connection and click properties. Then uninstall your protocols.
What do you mean keeps the configuration and loads it when you put it in? Is it just identifying the card and installing the windows driver for it. If so then it is designed to do that for "ease of use". If you have updated drivers for your nic then just go to device manager and install them from there.

I finally got the problem fixed. After experimenting with a bunch of different cards and cables I narrowed the problem down to a software problem. I don't know why the idea didn't come to me before, but I started turning of system processes one-by-one and found the one that was causing the problem. VSMON.EXE, an artifact of an old Zonealarm installation from who knows when, was blocking much of the network traffic out of my computer. With the process removed and Zonealarm cleaned up everything works just fine.

I don't know why the Zonealarm uninstaller left the folder with the service in my windows directory but at least its gone and everything works now. Thanks for all the help.