How to install old bootloader on Samsung Galaxy S2 to enable USB Jig?

Why USB Jig can’t reset custom binary download counter on my Samsung Galaxy S II? Hey, USB Jig is not working… Well, you might get a faulty USB Jig in this case but unlikely. Most likely, you have new bootloader that prevent USB Jig to reset custom binary download counter on your Samsung Galaxy S2. So how to reset custom binary download counter in this situation? Simple, install old bootloader on your Samsung Galaxy S2. And your USB Jig is back to business then.

How to install old bootloader on Samsung Galaxy S2?
The old bootloader installation process is the same as firmware installation using Odin. You can put the old bootloader tar file on either PDA or BOOTLOADER section. Then flash it. You can install new bootloader back after reset the custom binary download counter. But not necessary because nothing new in the new bootloader except disable USB Jig usage. Do visit XDA website if you need more information.

Installation guide – How to install firmware on Samsung Galaxy S2 with Odin? (Video)

Download old bootloader for Samsung Galaxy S2 I9100 here.

  • Baig

    Hi jayce,

    Could find the right topic for this so posting here…i am experiecing low mic volume while making calls on my SGS II. People on the other end keep asking me to speak up..Is there any fix for this?

    Am running stock 2.3.5 KI3

    Thanks in advance!!

    • Are you using case that block the mic on top of the phone? Try turn on speaker mode, it should be okay. It is a known issue ~ bad noise cancellation.

  • Baig

    No case i am using does not cover any of the mics…

    • Please consult Samsung Support in this case. Your mic might have issue then.

  • leo

    hi i have a bootloader problem my samsung s 2 while i was flashing a rom it switched off the phone and it won t start again with a usb jig can i fix the problem????

    • No idea. You can try.


    I was rooted with CF-root …
    Will this flashing causing me loss or something else i overlooked?

    • I did not hear people complain about CF-Root is causing issue so far.

  • theong

    i had updated my s2 via kies to 2.3.6 before..
    and now i had rooted, i tries to plug in usb jig and reset binary count, but it doesn’t work,
    did i need to flash back to the stock firmaware before I install old bootloader into my phone?
    or I can straight install old bootloader via odin at “bootloader” section without reflash to stock firmware?

    • Install old bootloader will do.

      • theong

        so i just need to install old bootloader without reflash stock firmware?

  • roy

    what will i do if i did wipe my phone Sgs2 i9100? thanks more power to you!

    • All data and settings will be gone then.

  • Seb

    Hi Jayce.

    First wanna say tnx for great guides, you rock. Im about to flash old bootloader for my sgs2. I requested the file on xda and received a file called “GTI9100 old bootloader. If I extract it I receive a file called sbl.bin. Should I put the unextracted file called old bootloader or the extraxted sbl.bin in PDA and flash?

    • Put GT-I9100_OLD_BOOTLOADER.tar.md5 in PDA or BOOTLOADER then flash it.

  • Rob

    Hi jayce!

    Do you have a link of the New Bootloader? I would like to install it back after resetting binary counter. Because I’m afraid the samsung guys might notice that I change something from stock. hehe πŸ™‚

    • Rob

      It’s ok jayce. I found it now. πŸ™‚

  • Andy Watt

    Hey there, before flashing bootloader do I need to clear cache ect or can I just put the phone straight into download mode and flash old bootloader? Cheers Andy

    • No need to clear cache.

  • Andy Watt

    Cheers m8 πŸ™‚

  • Andy Watt

    Hey Jeyce do you have a working copy of the old bootloader as the link one is broken any suggestions? Cheers Andy

    • Broken? I still managed to download it now. Which browser are you using?

      • Andy Watt

        Sorry not the link but oden didnt recogise the file it in pda or bootloader just managed to get a working one though and have flashed it back to old and now the jig works πŸ™‚ but check it out as I couldnt get that one to work. cheers Andy. Thanks for your help m8. bring on icecream sandwich when it comes out eventuallt lol

  • Rico

    Can I use the old bootloader on ICS roms, like LPQ??


    • Should be okay because I am still using old bootloader while testing ICS firmware.

      • Rico

        Hi Jayce, you told me you’ve been using it while testing ICS.
        Are these ICS flashed through CWM or Odin?
        Because using CWM, the custom firmwares don’t have the bootloader file, so I tried here and there’s no problem (I flashed an ICS custom firmware through CWM using GB 2.3.6 and it worked).

        My question is, have you tried flashing an official ICS firmware through Odin (PC version) and later used the old bootloader through Odin too? ’cause official ICS changes the bootloader file.

        Many Thanks!

        • Odin.
          Yes, the ICS ROM that I use is from XDA website. And it includes old bootloader.

  • Harry

    Hi mate, if i install the old bootloader does it go in the bootloader section in odin and after i have finished with the old bootloader how do i get back to my original bootloader cheers.

    • Rico

      Yes, it goes into bootloader section in Odin.

      I believe If you flash a new rom, like ICS, you’ll get the original back.

  • David Wilson

    Hi Jayce,
    I’m just wondering if you could give me some advice please mate?
    I am running 2.3.6 XXKI4 and I tried to install CM7.1. I forgot to Wipe Cache/Factory Data before installing and the phone got stuck in a boot loop. After a bit of a panic I thought I would re-flash the stock firmware. After that continually failed it got stuck on a screen saying There was a problem with the firmware upgrade. Please enter emergency recovery mode through Kies. Obviously that didn’t work. After numerous heart attacks I restarted the computer. Once that had re-booted I tried to reflash the stock firmware with Odin while holding my breath in anticipation… Success!!!

    Now it is all back but the custom binary count is at one. I tried the USB jig that I bought off eBay but it didn’t work. I saw this article so I used Odin to install the old bootloader but it still won’t work.

    Any suggestions???

    • If using old bootloader and still can’t reset counter, your USB jig is faulty.

  • Anish

    how can i get bootloader for bell Canada Samsung s2 I9100M (I9100MUGKG2)

    • Hi Anish, I don’t have it. And I have no idea can I9100M use I9100 bootloader or not. Try to consult others who have I9100M model at XDA website.

  • justin

    At around the middle intratech noted that firmwares below that point has old bootloaders right? So DXKL3 firmware do not need to flash old bootloaders as intratech has stated? Need help reply fast :X

    • No need unless USB jig is not working.

      • justin

        OK thanks.

        I do not need to use a jig for the stock firmware to work right?

        • No, it is only require when to clean custom ROM flash counter.

          • justin

            Thanks jayce:)

  • justin

    Hey jayce could u do a tutorial on how to flash back to new bootloader after flashing old bootloader for warranty purposes?

    • Hi justin, the installation process is the same as old bootloader.

      • justin

        could you give the links?

  • justin

    along the middle theres some links.

    so i just flash the old bootloader then flash the new bootloader tarball as stated by intratech?

    • Yes, after reset binary counter.

  • Chris

    Hey Jayce, Just wondering if this is how to install.
    1) Put SGS2 In Download mode.
    2) Put the GT-I9100_OLD_BOOTLOADER.tar.md5 in PDA or BOOTLOADER
    3) Flash it then i finish?
    4) use USB JIG to reset the CUSTOM BINARY DOWNLOAD thingy.

    • Hi Chris, please take time to study my SGS2 guides. You will get your answers. πŸ˜‰

  • joemar

    This tip was very effective works after rooting to 4.0.4. Thanks

  • bibin

    hi jayce,
    im new with updating softwares for my galaxy s2. apparently the older version of gingerbread has been removed and cant put in the ics. the phone is showing its boot screen and is stagnant. i cant use odin to upload a new bootloader as its not detecting my phone. wat can be done???

    • Hi bibin, can you still load Odin Download mode?

  • Jhonas

    Hello guys, my SGS II GT-i9100 soft bricket.
    Still can open odin mode, have yeallow triangle, but phone dont boot to using state.
    Tryed to instal old bootloader , but it fails

    Odin v.3 engine (ID:3)..
    File analysis..
    Get PIT for mapping..
    Firmware update start..
    NAND Write Start!!

    Complete(Write) operation failed.
    All threads completed. (succeed 0 / failed 1)

    USB jig not working, its just turning on factory mode and noth.
    Tryed instal 2.3.4 and 2.3.5.

    any sugestions what to do? :/

  • Jhonas

    also, cant get into ClockworkMod-Recovery or stock recovery mode , buttons vol up+home+ power but, dont react.

    • Hi Jhonas, you can try to install stock firmware.

  • Jhonas

    i cant get any of that from xda-developers πŸ™ download links dont work (files deleted)
    besides, dont remember what version my sgs II i9100 version is
    I bothet it from sweeden in 2011/09

    Can t you paste link where i can download stock firmware

    • You can try to get from SamMobile.

      • Deniz

        Hi Jayce,

        I have samsung galaxy s2 T989 i tried to downgrade from 4.1.1 to 2.3.6 but something goes wrong , my phone doesn’t start anymore , i push power buton but phone doesn’t start booting , I don’t know what to do , when i put my phone in computer odin read my phone …But i don’t have idea what to do :S , please can you help me ASAP my e-mail

        • Hi Deniz, do make sure that you are using the correct T989 firmwre (you can’t use I9100 firmware). Factory reset at recovery. Then install firmware with Odin.

          Please consult others for details at XDA Forum as I don’t have T989 model.

  • Jhonas

    Anyone ho have problem below, atention.

    Odin v.3 engine (ID:8)..
    File analysis..
    Get PIT for mapping..
    Firmware update start..
    Complete(Write) operation failed. All threads completed. (succeed 0 / failed 1)

    Try reinstal samsung drivers, try instal from another PC,
    use this drivers

    dont instal kies at all

    Reeapiting, if you CANT instal any kernel, any firmware and phone freezes on Yeallow triangle, try another PC, reinstal Drivers.

    ps. fynaly after 2 months i can use my phone again πŸ™‚

  • Vince

    Thanks man, I’ve been trying for weeks to solve this issue. It worked for me after trying almost everything.

  • guddu

    i have samsung sgs2 gt-i9100 on 4.0.4 …after rooting thru odin got yellow triangle…can i flash old boot loader to reset binary counter? Many thanks…..

    • Yes, or you can use Triangle Away application to do so too.

  • guddu

    thanks a lot,,,it worked on my sgs2 4.0.4…

  • guddu

    Dear Jayce my camrea on sgs2 after rooting not showing object in screen although able to click the photo and galary app not able to open storage and says sd card not mounted even though sd card is mounted…. do i need to reinstall 4.0.4 firmware ….please help

    • How did you root it? Rooting should not cause these issues.

  • guddu

    Dear Jayce ….as i am new to rooting i followed some post and successfully rooted it but cwm was missing so i followed this post

  • guddu

    galaxy-s2-root/how-to-install-clockworkmod-recovery-on-rooted-galaxy-s2-i9100….but my phone stuck in boot loader ..

  • guddu

    after that based on fran comment (i just tried to re root with CF-Root-SGS2_XX_XEO_LPQ-v5.3-CWM5 using odin.

  • guddu

    this worked first time plus cwm was installed when phone restarted and i didnt need to reinstall any apps.) after some time i notice camera issue…so i am not really sure which step might have caused this issue.

    • Try factory reset first. If still cannot solve, install another firmware.

  • guddu

    Dear jayce …thanks a lot ..factory reset couldn’t solved this problem so i have installed resurrection remix 3.1.3… camera and gallery working normally…

  • smartman

    hi there
    i rooted my galaxy s2 and tried to unroot it later to update the software, but unfortunately it did not work and i have got a fixed screen on my galaxy that shows a mobile device and a computer with a yellow triangle inbetween.
    i tried usb jib but no luck
    what should i do

    • Hi smartman, try to install firmware with Odin. If still cannot, try emergency recovery in Samsung Kies.

  • Smartman

    Hi there
    Kies does not recognize my phone
    And i tried to flash it with odin with no luck

  • Smartman

    If u could send me ur email i could sent u a photo of thr stuck screen

    • Sorry smartman, please consult Samsung Support if both Odin and Samsung Kies emergency recovery do not work for you.

  • Adnan

    My SGS2 is totally dead and I cannot enter the download mode at all ……
    Whats the wrong with it ? How to fix ?
    I flashed the wrong firmware( SGS1 ) to my phone ( SGS2 )and then it becomes bricked …..

    • Sorry Adnan, you can’t do anything if can’t load Odin download mode and recovery. Please send to Samsung Service Center for repair.

  • vanessa

    hi jayce, so I currently on jelly bean 4.1.2 xwlss. I updated from sammobile using odin from 2.3.3 gingerbread. now I want to go back to gingerbread. it doesnt have to be 2.3.3. any gingerbread is fine. can I downgrade it like when I updated to jelly bean with firmware from Sammy bile ? thanks. cos I confuse with the bootloader that people talk about. they say you cant downgrade from jb to gb cos that bootloader. please help me. thanks so much before

    • Hi vanessa, bootloader should not have any effect which Android version that you install. I have no issue using old bootloader on new Jelly Bean.

  • Greatful Guy

    This small bit of information, was a godsend and saved my bacon, I could not reset the 11 count I had on my SGS2 GTi9100. I Odin’d the boot loader above and used what I had thought was a dodgy Jig key, and Hey presto I can send my phone back for a guarantee fix at Samsung. Thank you once again for posting this simple yet effective fix, I’d been stressing all damned week after a bad Kies firmware update.

  • syak

    hi.i need your s2 from custom rom 4.3..then flash to custom 4.4.2..after flash 4.4.2, my wifi still working, but after restart my phone, my wifi cant ON..i try to downgrade to official ICS, but still cant ON..i dont think and im not sure that my wifi chip is burned, because i only ON wifi about 7hours/day..hope u can help me..thanks

    • Hi syak, you can restore back to stock firmware to confirm that.