connecting Vista and XP on network

For a long time, I had a Vista computer outside and an XP computer in my bedroom.

The problem was that my printer was connected to the computer in the bedroom.

After several months, something triggered me (probably just fiddling around) to change the workgroup name on the Vista computer to the same workgroup name on the XP computer.

And what do you know, I was able to see the other computer on the network and connect to the printer.

So that worked for a few weeks (or whenever) until yesterday. When I tried to print to the other computer, nothing happened. Then I noticed the computers no longer could see each other on the network.

The only thing I might have changed was that I had switch from my hub to a wireless router (for testing the wireless NIC on a computer I was working on), then I switched back to the hub.

When I do an IPCONFIG on each computer, I notice they have a different IP address for the default gateway.

I'm unable to ping the Vista computer IP address from the XP computer. But oddly, I'm able to ping the XP computer IP address (and its default gateway) from the Vista computer.

After I discovered the problem, I turned on network discovery from the Network and Sharing Center but that didn't solve the problem.

Don't know what gives?

So what I did was upload the file on skydrive and go to the XP computer to print the file. But then I saw no printer was installed on the XP computer. Print spooler service is not running it said.

Then I shut down and reboot and the printer is back. And was able to print.

I dunno. Maybe I'll try putting back the router to see what happens..

Maybe it's because I'm using a hub and the modem assigned different default gateways to each computer. But if I use the router, it'll assign the same default gateway to the router?

Sounds plausible now that I think about it..