If your on NTL what I did was:
Get to a command prompt. (START, run, cmd).
Type "ipconfig /release" (without the quotes, on the command line by itself).
Type "ipconfig /renew" (without the quotes, on the command line by itself).
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If that doesnt work then you might have to leave it for a few hours (overnight is best)...
Get to a command prompt. (START, run, cmd).
Type "ipconfig /release" (without the quotes).
Shut down computer.
Turn off computer.
Turn off all ethernet hubs/switches.
Turn off cable/DSL modem.
Leave off overnight.
Turn everything back on.
Then you'll get a new IP address from NTL.
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If your through a router
Log into the router's admin console. (Often
http://192.168.1.1/)
Release the IP address. (Method varies by router manufacturer)
Turn off router, ethernut hubs/switches, and the cable/DSL modem.
Leave off overnight.
Turn everything back on.