[Q] Samsung Galaxy S2 won't boot. Recovery mode not accessible. - Galaxy S II Q&A, Help & Troubleshooting

Hi all!
I have a Samsung Galaxy S2 which I since a week cannot start. It get stuck on the black/white samsung logo. I cannot enter recovery mode, nothing happens when releasing the power button after pressing volumeup+home+power buttons. I can however reach download mode. I'm not sure what caused this problem, one day I just couldn't start it. I read on forums that many similar problems seem to have occurred when upgrading android but I'm not sure this is the case here (unless the phone made an automatic update while I was asleep). I'm not sure what version of android I'm running, but I'm pretty sure it is at least the ICS.
I would like to hard reset my phone if possible. It seems to be easiest through the recovery mode which I cannot get into.. I read things about Odin, connecting the phone to the computer and downloading android to the phone but haven't quite grasped it. Could anyone explain this option for me or point me in the right direction? Are there other options?
I would appreciate any help, especially since my 1-year warranty expired a month ago!
Best regards,
Marcus

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marlu873 said:
Hi all!
I have a Samsung Galaxy S2 which I since a week cannot start. It get stuck on the black/white samsung logo. I cannot enter recovery mode, nothing happens when releasing the power button after pressing volumeup+home+power buttons. I can however reach download mode. I'm not sure what caused this problem, one day I just couldn't start it. I read on forums that many similar problems seem to have occurred when upgrading android but I'm not sure this is the case here (unless the phone made an automatic update while I was asleep). I'm not sure what version of android I'm running, but I'm pretty sure it is at least the ICS.
I would like to hard reset my phone if possible. It seems to be easiest through the recovery mode which I cannot get into.. I read things about Odin, connecting the phone to the computer and downloading android to the phone but haven't quite grasped it. Could anyone explain this option for me or point me in the right direction? Are there other options?
I would appreciate any help, especially since my 1-year warranty expired a month ago!
Best regards,
Marcus
Click to expand...
Click to collapse
Sounds like the symptoms of a NAND RW corruption. Try this http://forum.xda-developers.com/showthread.php?t=1457458

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Hi Marcus,
I had the same problem few days back.
If it's not broken by you trying something fancy, the best solution is to take it to service centre. If you have rooted your device, had installed some custom firmware or are not willing to visit the service centre for some other reason, please read ahead.
All I did was,
Installed USB connectivity drivers through Kies.
Installed ODIN 1.83
Ensured that Kies or any of its processes are not running in background.
Downloaded the official SGS2 firmware
Flashed the firmware through ODIN.
It took around 10 minutes for the full process and I was having my mobile up and running. Using ODIN sounds scary initially if you haven't used it. I have slowly started gaining confidence in it after using it a few times.
Please note that though the process is well proven to be safe, there is still an amount of risk involved.
Sent from my GT-I9100

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Download a siyah kernel(like v4.0.1) .tar file and flash through odin.
See if that makes it boot/lets you into recovery.

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Adarzannh said:
Sounds like the symptoms of a NAND RW corruption. Try this http://forum.xda-developers.com/showthread.php?t=1457458
Click to expand...
Click to collapse
I appreciate all of your answers!
Adarzannh: I tried the guide but when flashing using odin I get stuck on:
<ID:0/003> NAND Write Start!!
both when trying to flash the recovery package and the kernel. Any clues?
mananbdesai: where do I find the "official SGS2 firmware"?
theunderlining: is it enough just to flash a new kernel or do I afterwards need to flash ROM too?

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marlu873 said:
Adarzannh: I tried the guide but when flashing using odin I get stuck on:
NAND Write Start!!
both when trying to flash the recovery package and the kernel. Any clues?
Click to expand...
Click to collapse
A couple of things..ensure KIES is not running on your computer in the background. If possible delete it completely. Also ensure your phone is connected to a USB port directly on the computer and not via a hub or to a USB port on a keyboard or something. Odin is a finicky s/w..so..
Also, try different versions. If v1.85 doesn't work try v3.4
marlu873 said:
mananbdesai: where do I find the "official SGS2 firmware"?
Click to expand...
Click to collapse
Go to sammobile.com or a sticky in the Original Android Development section here..has links to all the stock firmwares.
marlu873 said:
theunderlining: is it enough just to flash a new kernel or do I afterwards need to flash ROM too?
Click to expand...
Click to collapse
Lol at underlining. if you flash a custom kernel like siyah, you'll be rooted and get CWM. Using that you can install a custom ROM.
Sent from my GT-I9100 using xda app-developers app

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And youll be safe from the 4.0.4 brickbug if you flash siyah.
You flash a kernel for various reasons like it has emmc cap disabled,you can tweak it etc.
You can flash siyah kernel and stop there.Or you can move onto a custom rom.
Whatever,when its done-backup your efs and make a nand backup.
And yesterday I was downgrading my wifes phone onto 4.0.3.I was using odin and kept getting "failed".After 3 attempts I realised I hadnt put the phone into download mode..........how stupids that......lol

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hi there, just wondering, after Flashing the stock firmware through ODIN, do you lose everything in your phone? i need to get all the notes that I have in my phone (notes from the samsung stock apps). I dont have any external sd card in the phone. thanks in advance for the reply.

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enquiry
marlu873 said:
Hi all!
I have a Samsung Galaxy S2 which I since a week cannot start. It get stuck on the black/white samsung logo. I cannot enter recovery mode, nothing happens when releasing the power button after pressing volumeup+home+power buttons. I can however reach download mode. I'm not sure what caused this problem, one day I just couldn't start it. I read on forums that many similar problems seem to have occurred when upgrading android but I'm not sure this is the case here (unless the phone made an automatic update while I was asleep). I'm not sure what version of android I'm running, but I'm pretty sure it is at least the ICS.
I would like to hard reset my phone if possible. It seems to be easiest through the recovery mode which I cannot get into.. I read things about Odin, connecting the phone to the computer and downloading android to the phone but haven't quite grasped it. Could anyone explain this option for me or point me in the right direction? Are there other options?
I would appreciate any help, especially since my 1-year warranty expired a month ago!
Best regards,
Marcus
Click to expand...
Click to collapse
Hi there sir,
Has the problem solved ? Care to share the solution ?
Thanks.

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i had the same exact problem, i tried flashing with odin n stock firmware but stuck in NAND write start, i didnt try flashing with PIT & repartition though, i couldnt be bothered anymore, so i took it to samsung service plaza, they told me the problem is in the main PCB (hardware issue), so all they did was replace that n it got fixed! i didnt pay because it's still under contract/ carrier warranty

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Can you get into downloading mode? It's by hold and pressing volume down+home+power
Sent from my GT-I9100 using xda premium

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it seems for some strange reason the phone wont turn on now. Wheni plug it in i get the blue flashing dot but its faint. Tried download mode and nothing.

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same problem
araz.rozh said:
Can you get into downloading mode? It's by hold and pressing volume down+home+power
Sent from my GT-I9100 using xda premium
Click to expand...
Click to collapse
my phone is stuck at the bootlogo too. but mine is rooted n running on biftor rom (jellybean) pls how do i flash with odin? thanks

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help pls.
Pls guys I have the same problem but like I said earlier mine occurred while I waS tRyna backup my ROM. Plss can I get a detailed guide on how to flaSh my samsung galaxy SII GT19100. ItS verion; jelly bean 4.12.Its rooted n runs on a custom ROM( biftor). Plss guys help. Thank you.

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tatchero said:
Pls guys I have the same problem but like I said earlier mine occurred while I waS tRyna backup my ROM. Plss can I get a detailed guide on how to flaSh my samsung galaxy SII GT19100. ItS verion; jelly bean 4.12.Its rooted n runs on a custom ROM( biftor). Plss guys help. Thank you.
Click to expand...
Click to collapse
I had a similar problem, stuck at boot with Biftor v12, which happened after I tried to update SuperSU binary through CWM/TWRP. I don't know why it stuck at boot and why it wouldn't reboot to Recovery. Download mode was still working, so I had no choice but to flash new kernel through ODIN and see if it works.
So if your symptoms sound similar to mine, here's what I did to be able to boot again:
I REPEAT, SIMILAR TO MINE. MY SOLUTION MIGHT NOT NECESSARILY APPLY TO YOURS.
1. Download a suitable kernel in tar.md5 format. I used PhilZ-cwm6 v4.93.6 for XWLSN firmware (see OP http://forum.xda-developers.com/showthread.php?t=1877270)
2. Download ODIN, if you don't have it, found here http://forum.xda-developers.com/showthread.php?t=2189539
3. Once installed, boot your phone in Download mode by pressing Vol Down+Home+Power together until you see a warning dialog. Press Vol UP to get into download mode.
4. Make sure ODIN is running, and NO KIES processes are running.
5. Connect your phone with USB cable to your PC.
6. In ODIN, you should see a COM port with yellow background.
7. Click the PDA button ONLY.
8. Select the kernel file you downloaded.
9. Press Start and nothing else.
10. If everything went as expected, your phone should reboot after a while with a working Recovery.
Only do the steps if you are absolutely sure. This worked for me, and I hope it gives some tips for your problem as well.

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Flash-IS-Bright said:
I had a similar problem, stuck at boot with Biftor v12, which happened after I tried to update SuperSU binary through CWM/TWRP. I don't know why it stuck at boot and why it wouldn't reboot to Recovery. Download mode was still working, so I had no choice but to flash new kernel through ODIN and see if it works.
So if your symptoms sound similar to mine, here's what I did to be able to boot again:
I REPEAT, SIMILAR TO MINE. MY SOLUTION MIGHT NOT NECESSARILY APPLY TO YOURS.
1. Download a suitable kernel in tar.md5 format. I used PhilZ-cwm6 v4.93.6 for XWLSN firmware (see OP http://forum.xda-developers.com/showthread.php?t=1877270)
2. Download ODIN, if you don't have it, found here http://forum.xda-developers.com/showthread.php?t=2189539
3. Once installed, boot your phone in Download mode by pressing Vol Down+Home+Power together until you see a warning dialog. Press Vol UP to get into download mode.
4. Make sure ODIN is running, and NO KIES processes are running.
5. Connect your phone with USB cable to your PC.
6. In ODIN, you should see a COM port with yellow background.
7. Click the PDA button ONLY.
8. Select the kernel file you downloaded.
9. Press Start and nothing else.
10. If everything went as expected, your phone should reboot after a while with a working Recovery.
Only do the steps if you are absolutely sure. This worked for me, and I hope it gives some tips for your problem as well.
Click to expand...
Click to collapse
Hi Flash-IS-Bright
I have the exact same problem with SuperSU on my rooted Galaxy S2. I updated the SuperSU app, and when I opened it, it recommended me to update the binary, I selected the CWM/TWRP option and then my phone tried to reboot but is now stuck. It can only access download mode.
In doing the process above, you only flashed the kernel? Did this totally work? And all your apps/messages were left intact on your phone?
Any help is appreciated.

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peshmann said:
Hi Flash-IS-Bright
I have the exact same problem with SuperSU on my rooted Galaxy S2. I updated the SuperSU app, and when I opened it, it recommended me to update the binary, I selected the CWM/TWRP option and then my phone tried to reboot but is now stuck. It can only access download mode.
In doing the process above, you only flashed the kernel? Did this totally work? And all your apps/messages were left intact on your phone?
Any help is appreciated.
Click to expand...
Click to collapse
when ur updating the binary u should always choose the 'Normal' thing instead of the 'CWM/TWRP' one ma8
if u flash a kernel it will not delete anything on ur phone, all u have to do is to select the right kernel like 'Philz' for example (if ur on a stock JB firmware) and flash the same through 'ODIN' and reboot ur phone

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Sun90 said:
when ur updating the binary u should always choose the 'Normal' thing instead of the 'CWM/TWRP' one ma8
if u flash a kernel it will not delete anything on ur phone, all u have to do is to select the right kernel like 'Philz' for example (if ur on a stock JB firmware) and flash the same through 'ODIN' and reboot ur phone
Click to expand...
Click to collapse
Thanks for your help. I've originally had Jeboo 1.2 kernel on my phone and tried to reflash that again through Odin. It passed, however I'm still encountering the same problem of the bootloop.
Would flashing a different kernel help? I'm on stock JB firmware but with a Jeboo kernel. I am happy to try another kernel (if that would not brick my phone)
Do you have any other suggestions to help me solve this?
Again thanks for your help

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peshmann said:
Thanks for your help. I've originally had Jeboo 1.2 kernel on my phone and tried to reflash that again through Odin. It passed, however I'm still encountering the same problem of the bootloop.
Would flashing a different kernel help? I'm on stock JB firmware but with a Jeboo kernel. I am happy to try another kernel (if that would not brick my phone)
Do you have any other suggestions to help me solve this?
Again thanks for your help
Click to expand...
Click to collapse
You could try flashing hawkerpaul's kernel wiper first and then install another stock kernel like PhilZ or Apollo, and see if that helps.

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Neat Rom lite,suddenly struck in boot loop after 1 month of operation.
Dear All,
I have installed the "I9100XWLSZ_NeatROM_Lite_v5.0.1" custom rom and after 1 month of successful usage, today suddenly the phone was dead.(probably due to autoupdates over wifi) . I tried to reboot, but didnt. Tried to restart but got stuck in the logo screen with yellow triangle.
Tried to enter recovery mode, but no use. Only download mode is possible.
Tried to flash the stock rom using odin, but no use, Nand write failed.
Can somebody help me how to come out of this situation. Shall I install a different kernal and see?
Regards,
Maka11