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New Visitor
geebear
Posts: 3
Registered: ‎01-02-2012

Connecting new computer to Internet

Hello,

I am trying to set up a new computer at a friend's home and am having trouble - hopefully this board can provide some assistance.

 

 Background:

 Brand new Windows 7 machine - I have previously connected it to my router and downloaded some software to the machine.

 

 I brought it to my friend's home where I swapped the network connection from their old computer to the new machine. (Modem is a Scientific American unit). I've power cycled the modem and tried to connect the new machine but with no success.

 

 I've called Comcast tech support and the auto assignment IP / DNS information is in place. The IP on the new machine does not seem to match the old one but my attempts to ipconfig /renew have failed. The unit simply sits on recognizing 'unknown' network and isn't able to get the Comcast settings. 

 

 I've even tried assigning the MAC address of the modem to the new computer. Do I need to give the new machine the MAC address from the old computer instead? Any help is greatly appreciated.

Silver Problem Solver
rog286713
Posts: 13,999
Registered: ‎06-17-2008

Re: Connecting new computer to Internet

[ Edited ]

ok so you are helping a friend who has a new pc.  you hooked the new pc to your router and downloaded some software to the new pc. So does your friend have comcast internet?  All you would need to do is take their modem that was working on their old pc and plug it into the new pc and it should work.  I got a new pc last week hooked it up to the router and the connection was instant.   are you connecting wirelessly or is this a direct connection?  if this is wireless have you run the set up cd?

 

what happens if you take the old pc and hook it up?  Does it work?

New Visitor
geebear
Posts: 3
Registered: ‎01-02-2012

Re: Connecting new computer to Internet

Hi,

Thanks for the reply. Yes, we are both Comcast customers -- my system has a router connected (which I connected the new computer to initially) and my friend's Comcast was connected directly to the cable modem.

 

This is all wired and no wireless connections are involved.

Silver Problem Solver
rog286713
Posts: 13,999
Registered: ‎06-17-2008

Re: Connecting new computer to Internet

so basically your saying it looks like your friends pc thinks its still on your network and just hooking it up wired to his cable modem direct gives you nothing?  in windows 7 look on the bottom right of the task bar there is a monitor with a wire icon.  If you click there it brings up the network and sharing center.  What does it say there.  ?  if you click on the full map what does that show?  If its your info try deleting that info and then restart the pc and let it find the new connection.  restart the modem also.  you sound like you know what your doing so this should not be new.  windows seven is a little different I don't know if your familiar with it. 

Contributor
martyscholes
Posts: 11
Registered: ‎01-02-2012

Re: Connecting new computer to Internet

Sounds to me like the SA modem is expecting the MAC of the old computer and ignoring the new one.

Put the modem MAC back to what it was then ask Comcast to do what they do to reset the modem's expectations. I seem to recall the billing was tied to MAC addresses at one point.

If Comcast can't / won't clear the modem, then you can try setting the MAC of new computer to old computer's MAC, or buy a cheapo router and throw it in between the computers and the modem.

As a rule, I avoid soft-setting MAC addresses.
New Visitor
geebear
Posts: 3
Registered: ‎01-02-2012

Re: Connecting new computer to Internet

It was what I expected -- Comcast's network was looking for the MAC address of the original computer and would not respond to the new machine until this MAC address was attached to the adapter.

 

I've run into this physical address issue when setting up routers in the past -- it is very inconvenient.

Connection Expert
EG
Posts: 42,982
Registered: ‎12-24-2003

Re: Connecting new computer to Internet

[ Edited ]

geebear wrote:
It was what I expected -- Comcast's network was looking for the MAC address of the original computer and would not respond to the new machine until this MAC address was attached to the adapter.

 


FWIW, the "network"/system doesn't "look for" the client MAC address. The modem does, and is the constraining factor here as it only allows one MAC address at a time to talk to the system. In order for it to recognize another device/MAC, its MAC address cache must be cleared by performing a proper powercycle/reset operation. "MAC addy cloning" should never be necessary. Perhaps there is a hardware issue with the modem or the powercycle operation is improper ?