I accidentally cut myself off the internet!
I have a 1TB Time Machine plugged into my TalkTalk broadband router. Normally this system works fine, but yesterday I noticed Time Machine backup hadn’t run for a few days. I pressed the reset button on the Time Machine and now I can’t even get on the internet. I’ve had to send this email from my neightbour’s house! Peter Rothery Time Machine is the part of the OS X operating system that performs the backup. The standalone networked disk you back up to is called a Time Capsule. It sounds as if your Time Capsule is acting as the Wi-Fi base station. The TalkTalk router probably has its Wi-Fi disabled and the Time Capsule plugs into it with an Ethernet cable and broadcasts the Wi-Fi signal around the house. It’s not uncommon for a Time Capsule to crash – they’re effectively small computers, with their own operating system inside. A power spike on the mains supply during a thunderstorm can do it, for example. When that happens you might still be able to connect through Wi-Fi, but the Time Capsule disk won’t be available for Time Machine. The solution is normally to turn it off and on again, to force it to reboot. If you press the reset dimple for a second, the Time Capsule goes into soft reset mode. This just resets the password and disables security for five minutes so you can log in and make changes. That wouldn’t have kicked you off the network. You must have held the dimple for more than five seconds and put it into hard reset mode, which clears other network settings. In particular, it tells the Time Capsule to request an IP address from the DHCP server on your broadband router. If you had turned DHCP off on the broadband router, this will have cut off the Time Capsule from the network.
It sounds complicated, but you can probably fix this easily. Plug your Mac into the TalkTalk router with an Ethernet cable and open AirPort Utility. Select the Time Capsule from ‘Other Wi-Fi Devices’ and click Edit > Other Options > Restore previous settings. This should get you back online.