YEP its the MAC address. Also known as the Physical Address.
i have a tower connected to my 3com switch. It works fine. If i connect it to the cable modem it works fine also.
The problem was in my laptop. when the laptop is connected to the 3com switch, NO LOVE. Then to the modem.. still NO LOVE.
someone mentioned turning off the modem for 10-15min so a new address will be given to the netcard. they also mentioned the MAC address.
HERES HOW I SOLVED IT.
Went to my tower. Which is my system that connects fine. Then go to Start>Run> type:cmd > then at the prompt: ipconfig /all.
I took the Physical Address: 00-11-5B-2C-BB-0A
wrote it down..
Then went to my Laptop to input the numbers.
Network connections> Rightclick> Properties> click 'configure' button (next to netcard name)
Click Advanced tab.
select 'Network Address' input number with no dashes '00115B2CBB0A'. press OK
And there you have it.
I have a Realtek RTL8139/810x Family Fast Ethernet NIC.
I guess turning off the modem for 10-15 works also to get a new MAC/Physical Address, but i havent tried it.
I did try everything else, patch, 'netsh winsock reset' , 'netsh winsock reset catalog', regedit, etc.. no love with those attempts..
Must be something with Realtek..
Hope that helps!!!

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