I got an iphone 4 last week. My home router is a Belkin 802 b/g with WPA2 security. Iphone had no trouble connecting to it initially or during the first few days. Yesterday, after leaving the house and coming back, the iPhone tried but refused to reconnect to wifi, saying "unable to join the network". Tried clearing the network settings and putting the password in again, same error over and over. Same issue after I rebooted the phone. Doesn't matter if I'm standing next to the router or across the house. This morning, wifi was working, I leave the house for a few hours, return and its the same error. Only solution is to restart the router. But that's not a long term solution. I have two PCs and neither of them has any trouble with the wifi. Would leaving large downloads (bittorrent) running in the background prevent the iphone from connecting? That's the only thing that might have been different this weekend. Any ideas?