Errors during Android update process (OTA)
No doubt, when updating Android software some you might face some problems, especially when a device has been rooted and (system partition) customized (nobody likes bloatware). Luckily recovery gives us some hints in cases when you are stuck on OTA. Those messages are usually accompanied with Android with ‘open belly‘ and red exclamation sign on top of it. Let’s look at the most common problems.
1. Incorrectly signed/changed/empty(wrong) file
It’s very unlikely that you will receive this kind of error while using file provided by a device manufacturer. It more likely that update.zip comes from an unconfirmed source. It fails on one of the firsts check made. Before any OTA get applied both signatures of the device firmware and OTA will be compared. If there is not match – the update won’t get applied.
Solution: Don’t use this update file. Wait for an official release.
2. Not there?
This is an interesting case. For some reason, your device is getting fooled that the update file has been downloaded and the upgrade can begin. Device reboots into recovery mode find command file (instruction set containing the location of the update, etc. More on: Talking to recovery mode) and then stops. Where is the update file?? This might be the problem of OTA client on a device or WiFi connection.
Solution: Try again?
3. Wrong start point
An incremental (type) OTA can be applied only to a specific build. What happens when the wrong version is selected? Apart from checking the signatures, OTA scripts verify that the build residing on a device is suitable for applying the update. In this case, if at least one of the properties is incorrect then upgrade is canceled.
Solution: None. User error.
4. Firmware alteration
Let’s face it. Rooting and getting rid of bloatware is generally good for device performance, however not when you counting for any future firmware updates. If the update is going to touch a part of the system you have altered it will fail, as the files checksums are being verified beforehand. In this case, unless the original firmware is restored, the update won’t work.
Solution: Restore to original FW (if possible) and try again.