'Safe IMEI repair' is always available, but depending on the current state of the phone, it might not work. All procedures also work on the latest software version. These models are already tested but the update works for many more. Odin, for example, requires Windows, so keep that in mind while trying to update the firmware on any Samsung phone. Moreover, make sure you have the latest Samsung Android driver package installed. Samsung maintains many region-specific and carrier-specific update...