No internet connection after XP SP3 update

I have a D-Link ADSL2/2+ DSL-2520U modem (without wi-fi). I lost internet after installing SP3. I've tried all the methods listed above (re-installing drivers, DOS commands, etc.). None worked. Rolling back to prior to SP3 didn't help. Reinstalling Windows XP didn't help.

What finally helped was, I accessed the modem settings thru Firefox (typing "192.168.1.1" in the address box of Firefox), then clicked on Management->Settings->Restore Default, and then clicked on the "Restore Default Settings" button. I then re-ran the D-Link installation wizard which is on the CD which comes with the modem. Internet now works with SP3.