yashsingh1/xdaforums huggingface dataset:
[Thinkpad Tablet General] tang1331726:
When downgrading from 5.0 to 4.4 but fails to enter into the UEFI interface, how to return from UEFI interface to the Android interface.

1, if the BIOS settings have changed, please return all changes, so you need to write down what options were changed.

2, long press the power button to shut down, press and hold the volume + and volume - and power on, enter the FastBoot mode, using data cable connection computer.

3, extract droidboot.img and bootx64 from 5.0 OTA update package, this forum post has given the web link of the firmware, please download it.

4, create a folder named “flash” in the desktop, and then put the extract bootx64 and droidboot.img into the folder, and then create a text document, input “CMD” in the text document and then save, Modify text file txt suffix for bat. Turn off all the useless software!

5, open the new text document.bat, then there will be CMD interface, input

fastboot flash osloader bootx64.efi

and then input

fastboot boot droidboot.img

6, Then the tablet into the driodboot interface, and then in accordance with the downgrade tutorial directly degraded. Be sure to remember to delete a little something in the flash-LtoKK-PVT-810.xml:

<command>
<string>fastboot erase data</string>
<timeout>120000</timeout>
<retry>2</retry>
<description>Erasing 'data' image.</description>
<mandatory>1</mandatory>
</command>
<command>
<string>fastboot format data</string>
<timeout>120000</timeout>
<retry>2</retry>
<description>Formating 'data' image.</description>
<mandatory>1</mandatory>
</command>

, and then flash flash-LtoKK-PVT-810.xml use flash-LtoKK-PVT-810.xml,

7, when flashed (flash-LtoKK-PVT-810.xml), you will find that the tablet restart card in the logo interface, neglect it and forced shutdown, then press the volume+ and volume- and power to reenter the fastboot mode,

8, and then flash flash.xml, you will return to 4.4.
[Thinkpad Tablet General] pregis:
Thanks Tang1331726 for this detailled tutorial !!

I'm downloading the 1.15GB file over a poor wifi link... but as I understand you are proposing me to downgrade to kitkat.

As I've never rooted my 830F before when in 4.X nor mdified the bios of it, and updated only thru OTA to 5.01 last week, I'm a little confused about what you propose me.

I should use the proposed rooting technique for 5.0

http://xdaforums.com/android/development/intel-android-devices-root-temp-cwm-t2975096

Using T4 option...

don't you think ?

Thanks Workdowg for the information.

I browsed XDA and google, and ain't find any information about going from Android version to windows and back...

Too bad as my sun wants to try the lenovo concept (form factor is just perfect in my oppinion), but he wants Windows (8-( ...
[Thinkpad Tablet General] workdowg:
To be clear. This is to fix the bios error when you upgrade to Lollipop and try to downgrade to KitKat? Also this worked on your 830F?
[Thinkpad Tablet General] Forever_n00b:
What's the fuss?!

This. I had rooted kitkat on a pal's 830LC. He update to an OTA (lollipop according to him) and got stuck in vicious boot loop. I downloaded YT2-830LC_S0184_150422_ROW and whatever I'd do, flashing system image would fail. Finally, changed force sparcing to 500MB, and suddenly, it's what's all the fuss?!? By the way, Windows 10 x64, used IntelAndroidDrvSetup1.9.0.

Thanks a ton :good:
[Thinkpad Tablet General] tang1331726:
yes, I had do it three times, all of tried are succeed
[Thinkpad Tablet General] pregis:
Thanks Workdowg, and Thanks tang1331726 for your patience.

My english might be incorrect, but as I per my understanding this fix is when you are stuck and only solution is downgrading from KK to LL.

My situation is somewhat different as I've succesfully ugraded, without any glitch, thanks to the timming Tip warnig (this is a gold one, I wonder how many RMA Lenovo will have to deal with !!)

My exact situation :

830-F

Lollipop OTA succesfully installed (5.01 July 10 2015)

Problem occur using SuperSU (2,40, 2,46, 2,49) after successfully booted tethered recovery.

Can you confirm me that I've to do the process described by tang1331726 to fix the E: signature error, and that I'll still be under Lollipop ?

ps: I guess there's noway to get Windows 8 or 10 on my 830F, altough 851F seems very, not to say tottally, hardawre similar.
[Thinkpad Tablet General] workdowg:
You are very welcome!

As far as the "E: signature error" please try posting in the Intel tethered recovery thread. Those guys should be able to help. Some people had luck by placing the SuperSU zip on the MicroSD and installing from there. Also try using the another recovery. I use TWRP on my 1050F.

We are trying to get Windows and/or Linux running on these Android based YT2's. Keep looking back here for more info...
[Thinkpad Tablet General] workdowg:
Well, it looks like i deleted them accidentally. I only have the one for the 1050F. I have all the current ota's for all the devices (probably why i deleted the others...) Maybe [MENTION=997923]ionioni[/MENTION] still has them or has access to them...

Sorry :crying:
[Thinkpad Tablet General] jumpup:
I wonder if this is different from what I have on-hand. I have extracted the Lollipop OTA and have been working with the different, flashable partitions while I work on this custom ROM.
[Thinkpad Tablet General] :
don't have/didn't had, don't know of leaked flashable stock rom for 830/1380 models (lollipop i mean)
[Thinkpad Tablet General] jumpup:
It won't be necessary for my ROM. It's going to be a CWM backup that will need to be flashed with the tethered recovery app.

I'll add info to the installation instructions if any prerequisites are needed (unlocked bootloader, etc).

Thanks to both of you for all the hard work and knowledge you have put together. Without it, I wouldn't have gotten this far. :)

---------- Post added at 05:46 PM ---------- Previous post was at 05:19 PM ----------

There are a few, reliable utilities that can convert NAndroid CWM (and TWRP, to a lesser extent) to flashable ZIP files.

I'll be testing the most recent LL OTA. Going back and forth with the Intel Phone app to dig into this.
[Thinkpad Tablet General] Davest87:
I have 830l and I lost the stock recovery mode (vol + plus power button), the tab boot normally when I try to enter in this mode. Today I receive the OTA, but I can't flash it. What can I do?

PS: 2 weeks ago I try to instal lc firmware, but intel flash tool doesn't recognize the fastboot mode.
[Thinkpad Tablet General] :
1. if you are on lollipop (and i assume you are considering that you talk about a recent ota) you can enter in recovery mode by starting with VolDown pressed from power off mode (also no usb cable should be connected)

2. if you cannot connect with intel phone flash tool then you have driver issues, uninstall existing drivers and install both files from here and try again (maybe a reboot after you uninstall the existing ones)
[Thinkpad Tablet General] jumpup:
[MENTION=5188579]Davest87[/MENTION] - What Windows OS are you running. You may need to disable driver signature enforcement. I'll explain how (a Windows 8.1/10 common issue)
[Thinkpad Tablet General] Davest87:
1. is this the recovery? attached image. It doesn't appear installation from sd or something like that.

2. THX, I will try soon
[Thinkpad Tablet General] Davest87:
I have windows 7 home premium. Can I uninstall lenovo smart assistant?
[Thinkpad Tablet General] :
no, that's lollipop fastboot and you are still on kitkat bios... oh boy

the normal ota update is not working for you? if you have modified your tab (root etc) you won't be able to update (with ota or by sdcard) so you should flash back your stock kitkat and try again

read the start of this thread on how to return to stock kitkat

having the kitkat bios you must flash the kitkat stock rom and then you will be able to update to lollipop

(how did you manage to have and keep the kitkat bios on lollipop :) )
[Thinkpad Tablet General] jumpup:
That's not the Tethered recovery. That's Lenovo's stock boot screen.

Can you check your drivers in Device Manager? What OS are you running?
[Thinkpad Tablet General] Davest87:
Thanks guys, now I haven't time to reinstall driver and try to flash the kitkat rom on tab, but I will try soon. I have windows 7
[Thinkpad Tablet General] :
you will have to flash your kitkat stock rom, the steps are here

next time you use the restore kitkat bios(because i can't see other way you could have this mix tho one can be inventive and find other ways) remember to read and do all the steps in the post not just run the tool :) (lollipop works with the kitkat bios yet some subtle incompatibilities will show, for eg. the reboot to target will not work so when the ota tries to reboot in recovery it will just reboot, so it's either kitkat bios & kitkat rom either lollipop bios & lollipop rom)

after you flash your rom remember to set your country code BEFORE you take the lollipop ota
[Thinkpad Tablet General] DewDrives:
when i'm flashing the kk rom, its just stuck on 13%.. the problem is with the fastboot.... in the 8% section tab will go to 25second sleep, but after that nothing happens except the tab will just restart....
[Thinkpad Tablet General] :
try and detail a little ...

what model? what rom were you trying to flash? what android are you now on (kitkat, lollipop?) you flash using intel phone? can you copy/paste in a file and attach the log from intel phone flash?

a quick answer is drivers, more exactly the Intel Android one, yet this is just guessing until you give more details

i managed to open the picture linked in the message

ok, it tries to start the fastboot mode, yet it cannot send any more commands... are you trying to flash kitkat from lollipop?

if so it won't work (flashing directly from lollipop will do just that, start your tablet because the kitkat fastboot files cannot load on a lollipop bios) and you must first downgrade your bios to kitkat go here for that then when finished flash again your kitkat rom
[Thinkpad Tablet General] DewDrives:
thanks for ur reply, yes i was trying to downgrade from lollipop, i already tried to downgrade my bios. but when i'm trying to downgrade bios, it shows (restore-kitkat-bios-830)

[PC] error when flashing os loader

[PC] have you started in DNX miode?

actualy i started in dnx mode itself.

anyway i think now i'm in a deep trouble. bcz i tried something else, and now when i start my tab in rcovery mode it showing a white screen with some options [contiue, select language, boot manager, device manager, boot maintanance manager etc.] :confused:
[Thinkpad Tablet General] :
thats the bios screen and yes, it shows when one tries to flash kitkat stock rom WITHOUT downgrading first the bios (what happens is that the ESP partition is flashed with a kitkat bootloader and the bios remains the lollipop one and when you try to boot the bios cannot load the incompatible bootloader and just skips over it and opens the setup screen... nothing to worry tho, as said is normal if you flash kitkat rom on a lollipop install without first downgrading bios). when in bios setup you can turn off the tablet with a long press of pwr button

do this:

1. install these (both) (most likely you have them but just to be sure), reboot the pc at the end

2. place the tab in DnX mode (screen MUST say "Fastboot starting..." and hang on that)

3. go to the restore kitkat bios thread and download the restore-kitkat-bios-830-1050-v2.zip file and run the exe inside following the instructions (again the tablet must have the "Fastboot starting" on screen when you run the tool) READ THE POST FIRST

4. when done restoring bios flash kitkat rom

ps. place the restore-kitkat-bios-830-1050-v2.exe on your Desktop and run from there if you still get that "error when flashing os loader"
[Thinkpad Tablet General] DewDrives:
Actually i read your post several times and never made a mistake on that. later i came to know that the problem was with the fastboot. so i googled about adb and fastbbot and i tried about 30 different approach to flash it and finaly i made it. thank youuuuuu soooo much guys, without dedicated peoples like u I'd never have got there. (now my only problem is that the firmware is an old kk software version) thank u once again workdowg and ionioni.
[Thinkpad Tablet General] :
so just take the ota's
[Thinkpad Tablet General] Davest87:
I tried, but intel flash tool doesn't recognize the tab in DNX mode, however the tool recognize the tab when is off (in charging). :confused:
[Thinkpad Tablet General] :
uninstall the phone flash tool you have now and download and install (accepting whatever asks you to) from here both files inside the zip, then try again
[Thinkpad Tablet General] Davest87:
It's works! :cool: I flash 830lc rom with phone call successfully, thank you so much. Now I am updating via ota for the newest firmware. These drivers and flash tool work great. You are awesome! ;)
[Thinkpad Tablet General] :
and afterwards resume from the dnx step (ie place the tablet in dnx mode and start intel phone flash tool and load the flash.xml file from your rom and start)

also you should put that sparse 500MB option in Phone Flash Tool (in File menu->Options check the box Force fastboot sparsing and in the box input 500MB, tho could flash even without it, never tried, doesn't hurt anyways to put it like that)
[Thinkpad Tablet General] Olivier:
Hey guys,

has anyone of you been able to build the LP kernel source? It seems to me that it's incomplete and broken.
[Thinkpad Tablet General] :
yep, even more out of the 5 or 6 tar.gz 4 don't even unpack correctly if i recall. i remember having compiled from an early source (and using missing files and modules from other phones), but only for a x86 kernel (truth told didn't tried further, was just me testing various stuff, right when i bought the tab 4 months ago)
[Thinkpad Tablet General] Olivier:
Cool, care to upload it to GitHub?
[Thinkpad Tablet General] :
lemme find it first ... i keep my linux stuff in a perfect order (NOT) :)
[Thinkpad Tablet General] DewDrives:
signal

after downgrading everything works fine, but network is not showing on the tab (yt2 830lc) . its showing "sim card not ready" :(
[Thinkpad Tablet General] :
what rom have you flashed? and what xml file you used? name them all if you tried multiple times
[Thinkpad Tablet General] smeborp:
Cant figure it out :(

I've been playing with my drivers all day trying to get my computer to recognize my tab. I have finally gotten to where i could run your tool (which I did and everything went swell). Well after this I have not been able to flash my tab as I have been able to in the past. The flash tool would recognize it for a second and then say my tablet was disconnected. (Said Connected on port 2/4). Ive been through multiple forums all day trying to figure out what to do. I've even tried the new flash tool that was posted above. ^^ Nothing is being recognized. My computer does in fact list the device when I use the command "adb devices"
[Thinkpad Tablet General] craniohm:
Maybe it could help if you try with another usb cable, from my opinion the lenovo cables are 1b
[Thinkpad Tablet General] :
if you can see it in adb devices it's a driver issue (highly unlikely to be hardware related). uninstall all that you have installed so far related to flashing (intel phone flash tool and drivers) reboot then install both files from this zip (accepting any prompt will give and using defaults)
[Thinkpad Tablet General] smeborp:
alright, so I've done that again to see if it'd show up and I got nothing. Previously when I have flashed my tab I've used this guide

http://xdaforums.com/thinkpad-tablet/general/guide-root-yoga-tablet-2-pro-8-10-13-3-t2930428

but with the new flash tool there is now way to just add the system image and flash, I have to have an xml. I'm not sure where to get it, or how to build the xml. sorry for all of the novice questions, I do really appreciate the you guys efforts.

Also I have already completed the process from this thread:

http://xdaforums.com/thinkpad-tablet/general/yoga-tab-2-830-1050-1380-to-kitkat-t3240487

I only started this process to get the new update in hopes that it'd fix the limitation of apps on the springboard.
[Thinkpad Tablet General] :
you didn't mention so far what is your model, so no specific files can be provided

you got nothing where? open a command window and:

- start the tab in DnX mode ("Fastboot starting..." on screen, VolUp&VolDown and PwrOn) and input fastboot devices

- start the tab in Fastboot mode (the one with the droidboot menu) and input fastboot devices

if you can enter these modes and your device is listed you should be able to flash, if it doesnt show then it's a driver issue (i doubt is the cable or hardware considering you can see it in adb devices)

there's no need to flash the files individually, the Phone Flash Tool does that for you, however if for some reason you want to, you can do it with the fastboot flash partition_name file_to_flash command, on larger files such as system.img use the -S sparse option too (fastboot flash -S 500M system system.img)

also you said that you downgraded your bios, in you Android open Contacts and input (in the search box) ####0000# and paste here what it says under Bios version

and atm i gues you still have Lollipop on your tab, no?
[Thinkpad Tablet General] smeborp:
I own the 1050f

My BIOS version is: BLADE_21.8686C.0004.R23.1504031154

Today I could see my device in fastboot and in droidboot. But I do not know how to obtain the XML that I am supposed to be using to flash my tablet with. I have the System.img, the Boot.img and the Recovery.img. How do I get the XML with what I have?
[Thinkpad Tablet General] timberfx:
Hi all,

anyone knows how to fix wifi problems, when a sim card is inserted. I mean when I insert my sim card, wifi will not see any wifi AP. I'd have to take the sim card out, get into the settings database | global table and either delete wifi_country_code or change the value to something like 'us'. After reboot wifi can see APs again.
[Thinkpad Tablet General] :
ok, so it should be easy now. you are on a IA32 bios (kitkat) so you should flash kitkat stock rom

use the below procedure:

================================================== =================

guide: flash kitkat 1050F stock rom

================================================== =================

1. download from here the 1050F kitkat stock rom

2. go to the extracted location and install both exe files from the drivers folder using defaults (if asked accept any installation prompt)

3. power off your tablet, by force if you have to (long press pwr button), now press and hold BOTH volume keys and keep them pressed, then short press Pwr button to start and release Pwr when the tab is starting (buzzing) but still keep volume buttons pressed, in a few sec your screen will display a "Fastboot starting..." message and it will hang on that message, you can now release volume keys (you are in DnX mode). you MUST get that "Fastboot starting.. " message on your screen before moving on (if you did not repeat the whole sequence from power off)

4. start the installed Intel Phone Flash Tool (in your Start menu you can find it under Intel->Phone Flash Tool), on the window it opens click Browse button and go to the folder where you extracted the downloaded file and in the YT2-1050F_USR_................. folder select the flash.xml file

5. click on "Start to flash" and wait to flash (take 3-5 minutes) when done it will reboot

6. after it finishes, on your first android boot go to Contacts and input (in the search contacts box) ####59930# and ONLY if it shows "unknown" (ie if it doesn't show a 2 letter country code) then you must set a country code go again in contacts and enter ####6020# and chose a country (yours or a close one, is irrelevant, this is not the language or timezone, which can be configured in the Settings) the tablet will reboot. you MUST have a country code set in order to be able to update using ota's (the ota update will fail without a country code and can brick your tablet)
[Thinkpad Tablet General] Wicked4u:
Kudos, m8.

Eu am 830F dar inca nu vad prea clara procedura de root.
[Thinkpad Tablet General] :
nu e greu, descarci tethered recovery si SuperSU

pune SuperSU.zip asa cum e pe sdcard

dezarhivezi ntelAndroid-FBRL-07-24-2015.7z undeva si executi launcher.bat, alegi un recovery (twrp e mai ok are si touch) si ca si trigger alegi T3 daca esti pe kitkat sau T4 daca esti pe lol, o sa restarteze tableta in recovery si acolo mergi la Install si alegi zipul SuperSU ce e pus deja pe card, el instaleaza restartezi si ai root
[Thinkpad Tablet General] murrder:
yoga 2 1050F break

Hello guys! I've successfully broke my tablet :( It won't go into OS, just stays blocked on the starting logo: "lenovo, for those who do". I'm a nub, and I really need your help. Can I do something to correct the problem? Or I have to buy a new tablet? Thank you very much.

PS: a lot of useful info you got here guys, keep up the good work!:good:
[Thinkpad Tablet General] :
mi-ai zis ca erai pe lollipop deci fa pasii de mai jos

================================================== =================

guide: flash lollipop 1050F stock rom

================================================== =================

1. download from here the 1050F lollipop stock rom

2. go to the extracted location and install both exe files (Intel Phone Flash Tool and intel Android driver) from the drivers folder using defaults (if asked accept any installation prompt)

3. power off your tablet, by force if you have to (long press pwr button), now press and hold BOTH volume keys and keep them pressed, then short press Pwr button to start and release Pwr when the tab is starting (buzzing) but still keep volume buttons pressed, in a few sec your screen will display a "Fastboot starting..." message and it will hang on that message, you can now release volume keys (you are in DnX mode). you MUST get that "Fastboot starting.. " message on your screen before moving on (if you did not repeat the whole sequence from power off)

4. start the installed Intel Phone Flash Tool (in your Start menu you can find it under Intel->Phone Flash Tool), on the window it opens click Browse button and go to the folder where you extracted the downloaded file and in the YT2-1050F_USR_................. folder select the flash.xml file

5. click on "Start to flash" and wait to flash (take 3-5 minutes) when done it will reboot

6. after it finishes, on your first android boot go to Contacts and input (in the search contacts box) ####59930# and ONLY if it shows "unknown" (ie if it doesn't show a 2 letter country code) then you must set a country code go again in contacts and enter ####6020# and chose a country (yours or a close one, is irrelevant, this is not the language or timezone, which can be configured in the Settings) the tablet will reboot. you MUST have a country code set in order to be able to update using ota's (the ota update will fail without a country code and can brick your tablet)
[Thinkpad Tablet General] pateken:
news for windows on android tablet?
[Thinkpad Tablet General] murrder:
Job done!

Thank you very much [MENTION=997923]ionioni[/MENTION], it worked like a charm! Bless you!!:angel:
[Thinkpad Tablet General] :
Să fi sănătos!
[Thinkpad Tablet General] workdowg:
deleted... Missed other answers... doh!
[Thinkpad Tablet General] Alivevil:
this tablet is not mine, and i don't what my friend's brother did to the bios exactly.

but i'm just sure that the stock/default firmware was lollipop.

trying this was not helpful,since i still get certificate validation failed error...:confused:
[Thinkpad Tablet General] :
1. you have not answered on whether you tried (both) the methods i gave you in my previous post (the ones in which we tried to boot in droidboot mode). on each try to detail as much as possible the exact steps you make and what is happening. it's hard for me to make any assumptions this way

2. can you still boot to the stock droidboot(fastboot) menu? (try alternatively with Pwr&VolUp or Pwr&VolDown) can you take a picture of it?

3. and another (maybe silly) one: are you SURE you have a Yoga Tab 2 model?