Unable to join the network "xxxxxxx"

Unable to join the network "xxxxxxx" on iPhone when trying to connect to wi fi
Solution :
1. Remove the password of router and try again
2. if not working, it is a hardware problem, it is the IC and the wireless antenna, get it replaced or fixed.

Run Blackra1n, but nothing happen

Run Blackra1n to jailbreak iPhone, but when it finished, nothing happen on iPhone..
Solution:
1.Restore the iPhone and then don't restore from backup
2.Run Blackra1n again

it works...