I have a latest generation Time Capsule (TC) that I connect to my ISP's modem, and everything was working fine - I was using the TC to access internet through both Wi-Fi (with a MBP, iMac, iPhones and an iPad), and there were a number of other devices connected via ethernet (both to the TC and the ISP's device).
I moved home this weekend, and we got an upgraded internet connection - this is provided through fibre optic to a router box. When it was installed, my MBP was able to connect to the internet via the TC. But a few hours later, seemingly as we tried to connect additional devices via Wi-Fi, devices just wouldn't connect. And before long, the TC itself was unable to connect despite the green light showing (it was saying that it had a self-assigned IP), although an ethernet cable connected directly to the ISP's router to my MBP was working ok (and my Apple TV started to work).
After reading online, I have managed to get the TC working again after disconnecting everything, waiting, connecting first the ISP's router and then the TC a few minutes later. I can now get online through Wi-Fi with my MBP, but... other devices connected to the TC are unable to connect to the internet (e.g. iPad via Wi-Fi, whilst the Apple TV and iMac won't connect via Ethernet or Wi-Fi).
On the iMac the IP address is listed as self-assigned (169.254.172.102 - this changes slightly if I try to connect directly to the ISP's router, but it still wont go online), Apple TV one is 169.254.123.15 and the iPad is 169.254.143.154. The Apple TV is connecting to the TC in such a way that I can stream the music from my iTunes collection on my MBP though...
On the TC, the settings are for connection through DHCP (IP address 18.104.22.168), with the TC's router mode off (Bridge Mode). The wireless network is WPA2 Personal (none of these settings have been changed since I moved home).
I'm going slightly mad, so any help would be much appreciated! It seems crazy that one day eveything works, and then after moving home I can only establish a single connection to the internet! My cable TV which is connected directly to the ISP's router via ethernet has been working fine through all of this btw.