Can't get HTC Thunderbolt to connect to my wifi network?

I just got Thunderbolt and I got it home trying to connect it to my wifi connection. Everything else in the house works fine with my wifi but for some reason this phone constantly cycles through "Connecting, scanning, disconnecting" over and over again. I messed around with router settings, and I know entered info right. So finally just decided to make it completely unsecure see what would happen. Same exact thing and have no idea why this is :/