iPhone 4S is loosing connection with Carrier after iOS5 update

I installed the update ios 5.0.1 tweak (9A406) and now is working perfectly i have an iphone 4S, i'm from México and my carries is movistar.

how you install?

i use WINDOWS... i try but the itunes not found the file. WINDOWS see .rar file.

You have to do a restore, because itunes do not recognize new build. I did this, but still no good, still getting random call failed and after that searching and no service. I also give my phone to repair service, but they find no failure. Can't believe that apple can't fix that. But maybe this is carier problem, but we will never know...

I can't install it!!

I already have ios 5.0.1 on my iphone 4s and now i downloaded the tweaked version that u linked and when i click on the file it only opens itunes and nothing else happens. My guess is that it will only work for older ios versions.

Or is there a way to install it anyway even if i have 5.0.1?

There are instructions: http://support.apple.com/kb/TS4148

To install this version what you have to do is open itunes , backup your information and press SHIFT + click on restore button (this is if you use windows) for Mac ALT + click restore button, it will pop up a window, search the file yu downloaded, select it and click open and your device will begin with the installation. I hope this helps

Ok guys now its installed and i can call, send text messages without any problems! 🙂 i'll let u know if it starts failing again. Thx for the help <3

Work for me too...

happy happy happy

9A406 seems to be working for me. Evening and night over and no sim card errors or lost carrier. :)

Did NOT work for me.

After 9A406 my iphone 4S still get no service and sim failure

Sad, very sad.

Btw i also got an operator update from my carrier. maby that's why it works for me.

I had the same problem for a long time. But Apple has published a tweaked update for it. Try this link:

http://support.apple.com/kb/TS4148

So far, it seems to have worked for me, too. (o2 - Germany) It is worth giving it a try!

I did the restore via itunes and it gave me the 9A405 build. It was supposed to give me the new tweaked version.. Now i still have no service issues and have to wait until apple officially fix this. So disappointed.

in the beginning it was the same for me.

For the first time I upgraded to 5.0.1 from 5.0, it installed 9A405. Then, i repeated it. I did a restore and it installed the latest version which is 9A406.

Now, I have my PIN-lock on and i did not lose the signal for 1 day.

How long did you wait from getting the 9A405 build until doing the second restore to get the 9A406?