Some of you had problems with the activation of the phones, that is, after activation you decode them and insert another card and the phone will give the error "Different SIM inserted". This is a possible solution to the problem, I haven't tried it and I don't know if it works (because I couldn't reproduce the problem), and you try it at your own risk.
There is a much simpler method, find information here.
Here's what you need to do to get rid of the error.
Step 1
Downloaded the Lockdown file from here.
Step 2
Connect to the phone via SSH using WinScp, you have a tutorial here, navigate to /private/var/root/Library/ and copy the “LockDown” folder to the computer.
Step 3
Delete the "LockDown" folder from the phone, unzip the archive downloaded in step 1 and copy the folder instead of the one in /private/var/root/Library/.
Step 4
Check if the "LockDown" file has the permissions set for 0644 (right click on it and select Properties).
Step 5
In Windows, delete the "LockDown" folder from the following locations, then reset the phone. If you do not do this, the phone will enter DFU Mode.
For Windows 7:
You'd delete the C:\programdata\apple\lockdown
For Windows XP:
C:\Documents and Settings\Owner\Application Data\Apple Computer\Lockdown
After the reset, the phone should work normally and without problems.
