Hi. I have a Samsung Galaxy S2. Since upgrading from Gingerbread 2.3.4 to Jelly bean 4.1.2, I cannot connect to 5g wifi. I can connect to 2g wifi no problem. Before the upgrade, I could connect easily to 5g wifi on Gingerbread. My partner also has a Samsung Galaxy S2 on Gingerbread and they continue to be able to connect to 5g wifi on the same router. I have tried manually entering the SSD and password, but no change. Sometimes, the phone does not detect the 5G signal on the scan for wifi networks, but other times it will. When I try to connect to 5g wifi, it will sometimes flash for a split second like it is connecting but then it will just say "saved, secured" or sometimes authentication error. Help ! I thought I was doing a good thing by upgrading, but it looks like I have just downgraded!!!