No 3G Signal after installing IOS 5

[Leash]

I have installed IOS 5 on my 3GS without any problem but now my phone can't connect to the internet via 3G only via wifi. Hopefully someone can help me fix my phone.

 

[NorfolkMustard]

in order of desperation:

make sure "mobile data" is enabled in settings >general > network

try activating airplane mode for a while

Turn it off (entirely, hold down the sleep/wake and swipe the red bar across the top) and on again

reset network settings in settings > general > reset > "reset network settings"

 

[Leash]

Thanks for the suggestions but none of them fixed the problem.