cannot use iphone 4 as personnal hotsport after upgraded to ios 6

Verify that your carrier supports Personal Hotspot for your device and that you have Personal Hotspot enabled on your cellular plan:

From Here > http://support.apple.com/kb/HT3574

Personal Hot spot

iOS System Requirements > http://support.apple.com/kb/HT3574

Understanding > http://support.apple.com/kb/HT4517

Trouble Shooting > http://support.apple.com/kb/TS2756

On this new IOS version 6.0.1 you need to enable following feature... "IOS just move the folders"...Go to

Setting -> General -> Cellular -> (needs to be enable Cellular Data) -> At the bottom shows Personal Hotspot, then after you enable this feature, now you gonna see on the General Settings Main Menu...

Settings-->General-->Reset-->Reset network setitngs

Setting - General - Cellural Data - "Internet Tethering" has to filled as same as Cellural Data APN.

without Intenet Tethering APN name , it keeps loading the personal hotspot.

Mine is working COOL now. I L MY phone.

Finally I found my problem, thank you so much batalgaa!!!