Posted here for max help:

Draytek Vigor 2710Vn - have had it a few years and it's been pretty much perfect. Today, played CoD on PS3 (wired) and got kicked out. I did what I sometimes have to do which is restart the router and do this by just pulling the plug out and sticking it back in again.

Since then, wired connections are fine but I cannot see the wifi signal - neither on iPhone nor on laptop. Searching for the wifi reveals nothing. SSID is not hidden.

I have tried to reboot the router via software, upgraded the firmware, disabled the wifi security, tried different channels and even went for a factory reset.

Why has it suddenly disappeared?
What can I do next?

Complete PITA because I'm now having to faff with this instead of getting ready for tomorrow's tutorial.

Might have glitched back to it's 'out of the box' wifi config. Is there a sticker on the bottom with a SSID and password? And is that SSID visible if you scan for wifi networks?

Try changing the wireless channel number? There's at least a dozen wireless networks near my flat and I'm getting this a lot with interference blocking out my wireless network - despite me sitting about 12 foot from the router. Changing channel can sometimes help in my case.

Tried all of the channels from 1 to 13. No luck.

WLAN light is on and SSID should be visible but can't be seen or detected.

Well I've found my old netgear router and have got wifi back up. Complete PITA.