Wifi connects and then immediately disconnects... Help!

[Scruffycro]

So just the other day, I noticed my phone wouldn't stay connected to one of the main wifi networks I use. I've been using it for months without any issues, and all of my other devices still work on it. I've tried various things, forgetting the network, restarting my phone, wiping the cache partition, and none of it has worked. I've been able to connect to other networks still, no problem, but this one just won't stay connected. It connects for 30 seconds or so, then just automatically disconnects. Anything else I can try?