Q: iPhone 4S is loosing connection with Carrier after iOS5 update

I had the same problem, but i read sowewhere that the microsim in the 4s is more critical.

My sim was a normal sim, cutted by hand.

This worked over a year fine with my iPhone 4. 

And the first week with my 4s also no problems.

Since 5.0.1 it didnt work anymore.

Totday i went to the Telfort shop (the Netherlands)

And there i got à new real micro-sim.

After it was activated (10 min) i had NO PROBLEMS anymore....

How hapiness could be so simple... ;)

I have same problem in malaysia i use digi!

Same Problem in Luxembourg with LuxGSM after iOS 5.0.1 update.

After upgrated to 5.0.1 my 4S has also started occasionally loose carrier. Also SIM card errors appear.

I have same problem in Viet Nam when update to iOS 5.0.1

I can't call or send message. Sad

I got the same error but it's over with new microSIM. Pls try a new microSIM from Vinaphone. Good luck :)

Well this link did indeed provide me with a solution that's been working:

It really does seem to be some kind of short in the sim, surprisingly never did it with IOS5 though ?? How bizarre ?

http://wooservers.com/20100710/fixing-iphone-4g-no-sim-installed-problem/

I have the same problem. i'm in Brazil, and in a good signal area, my iphone 4s are loosing connection adn signal from phone after IOS 5.0.1 update.

My phone crashes every time i received a call.

I mede my phone back! Solve this problem.

Same issue here. Bought phone in France, using it in Brazil.

I've filled a bug report at Apple (rdar://10452235), this is the best option to get heard (and have the issue solved).

Ok i'm in French West indies Caribbean island and my Carrier is Orange, i've tried a brand new sim yesterday not microsim, they cutted it for me, not successfull, today i asked a guy at the shop to borrow me his microsim from orange, those micro sim they sell in contracts, i tested it for about 15 minutes in my 4S 5.0.1 it worked flawlessly no error on sms nor 3G or calls, unfortunelly they didn't had anymore Orange factory microsim today, they ordered for me from another shop in 48h i'll be sure about it, they'll change the old brand new not working sim with the microsim for free, i'm waiting but i've faith because i saw it working with no problems, even with the bug when you pull out the sim from the phone the carrier is still working with signal, with the microsim, this bug is not happening anymore you see immediatly the message NO SIM....i didn't try to reboot the phone but that's a good beginning....

Same here after upgraded to iOS 5.01, it happens to both my iPhone 4s and iPad 2.

Can't believe apple screw another update

Reset network setting on iPhone and call your carrier to reset on their side.

Hi, I'm italian and I've got an iPhone 4S using "Wind" as mobile network operator. I've got your same problem: after the upgrade to iOS 5.0.1 my iPhone loses signal or doesn't recognize the SIM. I search for a while about this problem and now I know that's because some network operators, as Wind, don't directly cooperate with Apple and so, these kinds of problems may occur. Of course the operators need few day to adjust their networks and solve the problem.

However I think that, in these cases, Apple should advise users clearly - before the upgrade - about the possibility of this temporary incompatibility and allow the downgrade if anyone wants to try it anyway or mistakes installing the new release.

I have same problem in China  when update to iOS 5.0.1

I can't call or send message. Sad

IPone 4S +CMCC= Itouch 4S

Just to add some more information: my iPhone 4S was updated OTA to 5.0.1 with no issues at all - I had been restoring it from backup since my 2G.

My friend's 4S (which had been setup without iTunes) got to this state after 5.0.1 OTA update. His sim card works on my iPhone and mine still won't work on his, so it does not look like a sim card issue.