I have the exact setup shown here:
http://vonage.com/help_knowledgeBase_article.php?category=45&article=88

with 5 computers and they can all access the internet. Computers 1-3 are on the first router, and computers 4-5 are on the second router (which is called an adapter in the link above)

However, I'd like for all 5 computers to be on one home network, so they can shares files and printers. Currently both routers use their default settings with the exception of the 2nd router which has DHCP disabled. The 2nd router is set to obtain an ip address automatically. All 5 computers have the same workgroup name and the same subnet of 255.255.255.0.

What should I do to have them all see each other? Thanks!

Run the network wizard for XP.

In Windows HELP, click Index, then type:

walkthroughs

Below that double click "Networking"

Tells all about how to connect computers,
and setting up your network.
Run the Wizard on the Host computer, make
the floppy, and run the floppy on the
Client computers.

I'm assuming you don't have enough ports on the 'router' to connect all 5 computers.

You may need to get an additional switch or hub to add ports to the router

-- also, try the confiruation at this link:

http://vonage.com/help_knowledgeBase_article.php?article=61

thanks for all the help above - I have tried them all and my situation is unchanged. And you are right, 5 computers won't fit on one router. And the alternate configuration at vonage does not work for me. Its a known problem with their service and the more reliable solution is the setup I am using.

But this situation is not really vonage-related, its what anyone would face when casading routers. When you cascade them like I have are all computers supposed to be able to see each other automatically as long as they have the same workgroup? I am assuming there is some setting on one or both routers that I need to change. All 5 computers are seeing the internet, so that much is fine.

I've never cascaded routers before, but this is just a guess...

I'm guessing the 2nd router still has its NAT/firewall up, etc. If you can turn off everything in the router and just use it as a glorified switch, then that might work. Try setting either the 4th or 5th pc in DMZ mode and seeing how that works. If it works, then you know what the problem is. Maybe set a firewall rule to allow all incoming and outgoing traffic?

This might be a good one to post on the Networking forum if you haven't already.

I'm assuming that the first "router" is a router/switch and the second one is as well.

Can the computers connected to the separate routers share with each other? If so, the solution may be to hang a switch off the first router/switch and keep all the computers on this LAN circuit. The phones could go on the "telephone adapter" but I wouldn't put any computers on this..It probably establishes a second firewall that prevents the other computers from acsessing these computers.

"Can the computers connected to the separate routers share with each other?"

No they can't, and that is all I want to do that I currently can't.

same workgroup is great as well as SUBNET mask. But what are the IPADDRESSES???
Especially those off the 2nd router? They all need to be in the same ip range. 192.168.0.x for example.

Do a ipconfig on the 2nd routers pcs and report back what their ip is vs the ip of the station off the 1st router.

SOHO routers are not designed to be chained/nested. Proper configuration would have a switch where you have the 2nd router.

ip addresses:

1st router
192.168.1.100
192.168.1.101
192.168.1.102

2nd router
192.168.15.100
192.168.15.101

are saying I should change the IP address ranges of one of the two routers? Which one? Thanks.

I have a seven port switch behind a router with only one port. Then there is another 5 port switch which is connected to one to the ports on the switch. This setup allows up to 11 computers to all be on the the same workgroup. Possibly your problem may be that the router is set to only allow the amount of addresses equal to the amount of ports. Change the setting to the maximum, which I believe is 255. You should be able to piggyback as many computers as that. All we use is TCP/IP. This is all connected to a cable modem.

You need to get rid of one of the routers and get a network switch. Switches don't have nat firewalls like Routers do. I don't see the set up on the page you gave but I don't have flash installed so maybe that is why. Switches are like a straight line to your router without any network address translation. I bought a 4 port switch for $10 after rebate at office depot. With it and the 4 port router I can hook up to 7 computers. Not 8 because one port on the router is used by the switch.

You can turn your 2nd router into a switch by using a crossover cable from router1 lan port to router2 lan [not wan] port.

Turn off dhcp on the 2nd router.
You have two choices now. You can use the dhcp from the first router to assign the ip addresses or do static assignments for the two pcs coming off the 2nd router.

So change
192.168.15.100 to 192.168.1.103
192.168.15.101 to 192.168.1.104

"Turn off dhcp on the 2nd router..."

Okay I did that.....

"You can use the dhcp from the first router to assign the ip addresses or do static assignments for the two pcs coming off the 2nd router.

So change
192.168.15.100 to 192.168.1.103
192.168.15.101 to 192.168.1.104"

I did this, but may not have done it correctly. I changed the IP addresses from within winxp's LAN properties > tcp/ip properties, using 255.255.255.0 as Subnet and 191.168.15.1 as the gateway. I rebooted and got no connection. Then I changed the gateway to 192.168.1.1, and also had no connections. Was that right or are their other steps?

Listen to wanderer, particularly on the CROSSOVER CABLE part. Also set dns settings to same as gateway. OR do it right and get a switch.

The problem is that the 2 routers are on a different network. Try to ping from 191.168.15.* to 191.168.1.*
If you get a reply, then its OK, if not you have to add a route
Do this in a command box and type ROUTE ADD <destination ip-adres> <netmask> <gateway> on all your PC's

Greets