Sero 8 - Trouble updating to Stock ROM
So I'm fixing some Sero 8 tablets for a friend. Two of the devices are build E2281E0705B1V19, while the other was recently E2281E0705B1V20 that is now updated to E2281E0705B1V21. The two older versions cannot connect to Google Play because of a handshake error and will not detect the latest OTA updates.
Because I dunno how to fix this, I'm trying to install a dump ROM of either v20 or v21 builds. I installed MANY drivers and was only able to get "adb" to detect and not "fastboot" (win 7). I gave up on that method and was able to successfully install TWRP on both devices; while I could not on the newer v21 build in a attempt to copy that backup on the others. I tried to install AndroidFanatic's Stock Rom Dump through TWRP and was able not to because it was missing a m5d file of some sort.
At this point I am stumpted as to what else to do. Because I do not have an avaliable TWRP backup for either build v20 or v21 and cannot find the proper driver for the "fastboot" function on Windows 7, I feel like it is time for me to ask for assistance! I've spent two whole days just trying to get these tablets working on a up-to-date stock ROM and I'm thinking about just returning the darned things...
Can anyone help me?
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UPDATE 1:
I was able to figure out what program to use, you need "AndroidTool" to install Android Fanatic's Stock Rom. Not sure if we're allowed to share links outside of this website, but I found a useful guide here that helps explain what drivers and tool to download and provided links.
During the installation process, I used abdul_pt's Unofficial TWRP to flash TWRP first (as installing Fanatic's Rom first led to an error). Then I installed Fanatic's Rom afterwards successfully (if it doesn't work, re-flash TWRP or try clicking the "LowerFormat" button on AndroidTool, then retry). After this, rebooting the system will leave it hanging on one of the startup screens. You need to reboot into the system recovery, which will now be android default, and choose to "wipe data/factory reset". Reboot the system (yet again) and now it goes back to the same screen, wait a good long while and you will be redirected to the startup screen!
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UPDATE 2:
So... I still cannot access Google Play Store even when setting up an account. The google accounts fail to sync on the two, newley updated v21 devices just as it had with the previous v19 build versions. I assume this has to be a hardware issue, as I completely wipped everything from the system and re-installed an updated version. It sucks that I spent 3 days on this project just to find out there may be a hardware issue I cannot resolve. :|
I ended up returning the tablets; Mission Simi-Failed!
Because I dunno how to fix this, I'm trying to install a dump ROM of either v20 or v21 builds. I installed MANY drivers and was only able to get "adb" to detect and not "fastboot" (win 7). I gave up on that method and was able to successfully install TWRP on both devices; while I could not on the newer v21 build in a attempt to copy that backup on the others. I tried to install AndroidFanatic's Stock Rom Dump through TWRP and was able not to because it was missing a m5d file of some sort.
At this point I am stumpted as to what else to do. Because I do not have an avaliable TWRP backup for either build v20 or v21 and cannot find the proper driver for the "fastboot" function on Windows 7, I feel like it is time for me to ask for assistance! I've spent two whole days just trying to get these tablets working on a up-to-date stock ROM and I'm thinking about just returning the darned things...
Can anyone help me?
---------------------------------------------------------------------------------------
UPDATE 1:
I was able to figure out what program to use, you need "AndroidTool" to install Android Fanatic's Stock Rom. Not sure if we're allowed to share links outside of this website, but I found a useful guide here that helps explain what drivers and tool to download and provided links.
During the installation process, I used abdul_pt's Unofficial TWRP to flash TWRP first (as installing Fanatic's Rom first led to an error). Then I installed Fanatic's Rom afterwards successfully (if it doesn't work, re-flash TWRP or try clicking the "LowerFormat" button on AndroidTool, then retry). After this, rebooting the system will leave it hanging on one of the startup screens. You need to reboot into the system recovery, which will now be android default, and choose to "wipe data/factory reset". Reboot the system (yet again) and now it goes back to the same screen, wait a good long while and you will be redirected to the startup screen!
----------------------------------------------------------------------------------------
UPDATE 2:
So... I still cannot access Google Play Store even when setting up an account. The google accounts fail to sync on the two, newley updated v21 devices just as it had with the previous v19 build versions. I assume this has to be a hardware issue, as I completely wipped everything from the system and re-installed an updated version. It sucks that I spent 3 days on this project just to find out there may be a hardware issue I cannot resolve. :|
I ended up returning the tablets; Mission Simi-Failed!