Network Crashes

I have a home network with two Win XP desktop computers (both Dells) connected via ethernet, one Mac laptop via wireless Airport and an older Toshiba with Win 98 via a PCMCIA wireless card. All running on static internal IP address'. Wireless router is an SMC 2804 Wireless Broadband Router. I can access files between all computers and even print to my Brother laserjet and Epson inkjet through the Hawking print server, also a statci IP. Read on for the problem...

A few months ago I helped an out of town friend set up a streaming webcam on his computer using a program call Broadcam made by NCH corp. His laptop computer runs on Vista and to help him set up I installed the same app on one of my XP desktops. After figuring out how to set it up and make it work properly on my machine I relayed the procedure to him and we got everything working properly. It's basically establishing an open port on the router to allow the video stream out from his local network IP to the public IP from his ISP and onto a web page which has a link to follow to view the video stream. For over a month the application and process ran without a hitch from his home over his wireless network.

Fast forward to a couple days ago when he is in town and wants to use his web cam from my house over my wireless network. My intention was to shut down the XP machine I have running the web cam software and use the same static internal IP from that machine for his Vista laptop since my router port for that internal IP had already been established. In trying to establish the proper settings on his wireless NIC I was unable to gain access to the internet, his computer saying that network access was local only.

Now for the weird part. I soon noticed that NONE of the other computers on my network had web access, no email, no messenger services... nothing. I couldn't even access my router admin page through it's gateway address on the internal network. It's as if by connecting his computer to my network it effectively rendered the entire system useless. I tried resetting both the modem and router multiple times, using different internal IP address' than that of the XP machine I used to help set up the program. Even trying to use DHCP settings..all to no avail. The only way to get the network back online was to shut his machine down and reset the router and modem. I am baffled as to what caused all this.

A few other facts that may help diagnose. The Vista laptop (an HP) has a built in wireless card using 802.11 b/g/n. My SMC router does not support 802.11 n, only b/g. Could this cause the conflict? Is the router too old (almost 8 years) to be compatible with his newer (less than 2 years) computer? Could this be a Vista issue? I know XP far better than I know Vista. I'm at a total loss as to how to figure this out. I appreciate any insight you may have.

While not an IT expert, I have set up my own network and that of a few friends so I have a decent working knowledge of network set up and maintenance. If there is info that my be helpful to know, please post here and I will reply providing whatever info may be helpful.

Thanks again in advance for any light you can shed on this problem.

 

Thanks for the fast reply...

1. That's what I thought as well.

2. When setting up wireless NIC on his computer to work on on my network I chose manually assign IP (static) and DNS and did not choose DHCP for either of those services. Is there another DHCP setting I should be looking for? Again, I'm not well versed in Vista.

3. Will definitely do a scan. Any recommended apps for that? Norton? Macafee?

4 & 5. I tried assigning a different IP. Original was 192.168.2.120...tried many others up and down from there. No luck. Tried the DHCP option also. Thought I would let it assign and then use that IP to forward the correct port. The problem there was I couldn't get into my router to do the forwarding. Something was preventing access. From his computer as well as others on the network.

The only way to get back to a functioning network was to shut down his machine and restart the modem and router.

Thanks again..will look into other DHCP services and network malware.

 

Are you sure you are setting the correct adapter on the Vista machine? They have a bunch of them.

 

Yes...there are only two. One for the built in ethernet, the other for the built in wireless card.

 

Positive about the IP...

Dell #1 192.168.2.110
Dell #2 192,168.2.120
Apple Laptop 192.168.2.115
Toshiba Laptop 192.168.2.130
Print Server 192.168.2.30
Router Gateway 192.168.2.1
Router gateway has DHCP enabled, address pool of 192.168.2.100 through 192.168.2.199

I used 2 as the third number just to be different. Does it matter since the rest of the network uses the same addressing? I was under the impression I could use any number between 1 and 255 for the first three numbers as long as they remained consistent throughout the system.

On his Vista laptop I was making IP setting changes to the ipv4 section of the wireless card properties. Should I be looking at the ipv6 as well?

Thanks again Tony. I appreciate your input.

 

I have reconfigured network as you suggested.

Router stays as 2.1
Wired and wireless comps are in the 2.10 to 2.90 range
Print server is 2.91
DHCP pool is set for 2.100 to 2.253

Won't have another chance to test system with his HP/Vista laptop for another week or two when he returns to town. Will post back here with results when available.

BTW, router is SMC, not a Linksys. No mention on admin page of default range for static or wireless IP pool. I manually set DHCP pool to 2.100 to 2.253. it's all up and running again. We'll see what happens next time i try to connect his computer to my network.

Thanks to everyone for their input. This site rocks!!!