[Nexus 7 3G Android Development] hannibal585:
I am sorry, I am am here in the wrong section, the device is WiFi only. the fact is, for personal reasons, it is very important that i do not loose this tablet. and in the panic, i happened to land here. but you guys are sweet. thank you so much for understanding.

I will first try to answer briefly to question you ask:

I have never tried to revert back to factory image before.

I can not see the fastboot version, it does not show it. I got it about 6 months ago, together with DB v. 1.0.31.

before trying to flash any version of anything -i need to make sure that the tablet will be able to boot to bootloader.

now i will what happened (trying to be brief and to the point):

it was running CM11 nightly a couple of days old. It had bootloader 4.18.

after it froze at google logo on normal boot, i tried to get to recovery mode -where i got a blank display. so i was only left with bootloader.

i thought i would have to start by a fresh factory image. followed a guide in this forum, i downloaded the 4.4.2 image, typed fastboot commands step by step. while flashing the bootloader, it came with an error -i am not sure any more of the exact message. I could not understand it, i thought i had done something wrong. so i kept on trying.. I remember that i tried to lock and unlock commands, and tried to flash again.. I tried writing system image. I then went back to reading the forum messages. I still don't understand it. folks are writing the bootloader in the kot49h has an error. I do not understand that google would still make it publicly available for download if it was causing so much error/confusion.. I then downloaded and tried to flash different versions (4.23, 4.18), including the one that comes with jwr66v. I keep getting the same error message:

writing 'bootloader'...

FAILED (remote: (Unknown error code))

current situation:

right now, it still is as it was 4 days ago (in the same bootloader mode). the dispay shows the usual bootloader screen + two lines of 'signature mismatch' in the upper left corner.

my understanding is, if somehow I had erased the existing bootloader I should not reboot it, it would be bricked. I then do not understand the point in having the possibility to type such a command..

more?

I am not happy to write long messages in the forums. i also want to avoid any confusion. i live in a place (oh hell, it is called kathmandu), where the power supply is, politely put, irregular on top of scheduled 12 hours of power interruptions a day.. Reason why i choose to run knoppix on an ext4 partition. It made sense to download a standalone version of 'fastboot executable' compiled by someone nice on the Net.

am i repeating myself?

brief, should i try to get a proper version of the adb/fastboot. could it be the problem. i personally have a feeling, it is not.

Either I need to make sure that it will reboot at least bootloader or successfully write a new boot loader. so far I have tried 4.23 with the correct md5 ad mentioned in some guides. I have also tried to overwrite 4.18.

thank you for your patience. please help me.

to write everything publicly

i bought this for my young kid, we have been both very happy to own it. it would work independent of power supply, it was portable.. we are both very disappointed.. he can not look up wikipedia for his school. STOP.

regards