Iphone 4s does not reconnect to vodafone data when wifi switched off

Standard troubleshooting steps are as follows:

Power the iPhone off and on.

An iPhone reset.

Restoring your iPhone with iTunes from your iPhone's backup.

Restoring your iPhone with iTunes as a new iPhone or not from your iPhone's backup.

If no change after these steps and after trying to new SIM card from Vodafone to rule out a problem with the SIM card and after contacting Vodfone to ensure there is not a problem on their end in regards to your line/number - nothing needs to be reset on their end, your iPhone has a hardware problem.

Read the rest of what I provided which incudes more than just powering the iPhone off and on.

If no change after ALL the steps provided, your iPhone has a hardware problem.

Same here! It isn't a hardware problem. If it would be a hardware problem than apple needs to change alot of phones in germany. It's a known problem in germany. And it doesn't depend on the provider. So hopefully apple will fix it with an update or something! 700 Euro iPhone and nothing works! It's fine! Why does Apple so much to hide this 4S "revolution" secret. Deliver out some Test IPhones to the provider to check out there compatibility with the radio network and finally nothing works! Apple insert two antennas and they reduced the reception to zero. Next antenna or iOS5 gate?

Same problem here in Sweden. Lose the signal (i.e. in an underground garage), and there is no reconnection afterwards. Tested this yesterday, and after 5 hours there was still no reconnect, despite the fact that I was in an area with full signal capacity.

Will try the manual carrier selection instead, but that's far from ideal.