I had an odd problem with my own PC.

The internet suddenly dropped out.

I noticed my tp-link router had reset itself (its not done before), so I waited a minute for it to reconnect with the internet, but still no internet.

I reset the router and the adsl modem, but no internet.

I restart the PC, but still no internet.

I try my other PC: it works fine.

I do ipconfig: the IPaddress and gateway address looks ok.

I shutdown my personal firewall: still no internet.

I check the router: its not blocking anything…

I do an ipconfig /all on my PC, and on the other working PC: hey, there is a difference: the DHCP and DNSservers were set to 192.168.0.1 (my router is 192.168.0.122, and my PC is 192.168.0.16 (the DHCP pool goes from 12 to 65, so nothing should be using that IP address).

I do ipconfig /release, then ipconfig /renew, and everything sorts itself out at last! 

Its odd that a PC restart didn’t fix the problem… another mysterious XP networking problem.

A day later, the same problem happened again.

This has happened 1 or 2 more times in the last month, but I cannot pinpoint it (I have installed and upgraded some software, so that is another possible cause)…