Rooting Galaxy S2 - Dummies Guide

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  1. Shotgun84

    Shotgun84 Well-Known Member

  2. cybaree

    cybaree Member

    hi I want to know if I update my phone to ice cream via my phone software update will it brick my phone or lose root? Also any ideas why my phone just reboot itself every now and then?
  3. Shotgun84

    Shotgun84 Well-Known Member

    I'm not too sure if the ota option will work as you are rooted. If it does work it won't brick your phone but you will lose root. Random reboots are usually caused by your firmware. On some of the older firmwares I had the problem quite frequently but the problem disappeared for me with the 2.3.6 updates.
  4. cybaree

    cybaree Member

    Ok so if I do update will I lose titanium cause I have the paid version that I don't want to lose and then can I reroot with ice cream updated.
  5. ironass

    ironass Well-Known Member

    If you are considering flashing ICS to your gingerbread, rooted phone, I would recommend a full wipe of both phone and Internal storage, prior to flashing ICS. After the boot into ICS you will then be able to sign in to your Google account and re-download Titanium Backup Pro.

    Of course before commencing such actions, you should make both a nandroid and Titanium Backup that are saved to your external SD card.
  6. TaKeNUK

    TaKeNUK New Member

    Please help guys. I think I killed my S2 :(

    It's a the GT-i9100P through o2.


    PDA i9100PXXLPH
    (Need the rest?)

    I rooted as per the instructions given in the original post, Using CF-Root-SGS2_XX_OXA_LPH-v5.2-CWM5

    The root all appeared to go successfully. The phone went to reboot and brought up the i1900 Logo with the warning logo beneath. But after that the screen is just black, no sounds or anything.

    I tried once again via odin, Pass again. But still the same problem.

    Oh what have I done :( Please please help!
  7. ironass

    ironass Well-Known Member

    Hello and welcome to Android Forums TaKeNUK! :)

    Just to clarify...

    You have a Samsung Galaxy S2 GT-i9100P variant with NFC on the UK O2 network but with Mobitel, (Slovenia) carrier branded firmware installed on it, which I guess you flashed with Odin?

    Have you got the original, full, kernel version that came with the above?
  8. TaKeNUK

    TaKeNUK New Member

    Hello Ironass! Thankyou for your welcome and reply :D

    I do indeed have the o2 Branded Galaxy S2 NFC (i9100P)

    The firmware installed was updated last week via Samsung Kies.

    Very confusing to see that it's actually another carriers firmware?

    I do not have the original full kernal unfortunately. I didn't know how to back this up, or if it was indeed possible. So I just rooted the phone with CF-Root-SGS2_XX_OXA_LPH-v5.2-CWM5

    After three more attempts with the same LPH Kernal this morning I tried using CF-Root-SGS2_XW_O2U_LP3-v5.4-CWM5 which seems to work ok!

    The parts o2u and LP3 seemed similar to the CSC i9100Po2ULP4 which is listed in my phones version.

    Have I done the correct thing? Many thanks.
  9. ironass

    ironass Well-Known Member

    I have replied to your PM's but, in short, it would appear that your phone, purchased through eBay, came with Mobitel, carrier branded firmware which is why you could update via Kies last week, since O2 has not released their ICS firmware for the P variant yet. Glad you have it rooted now!

    Congratulations! :congrats:
  10. sntaylor

    sntaylor Well-Known Member Contributor

    Can't help but feel this post should maybe be a sticky?!?

    It is what I used to finally root (been considering it for about 4 months now but the Mrs has kinda prevented me from doing it, till now :-D)
  11. Shotgun84

    Shotgun84 Well-Known Member

    We have far too many helpful threads to sticky them individually. There just isn't the room. So they all get sticky'd here
    sntaylor likes this.
  12. Bailzebub

    Bailzebub Guest

    Somehow i've messed up my attempt at rooting.

    I have an Orange phone I9100P with the latest ICS update done using Kies. was the kernel i used, and now sadly it just doesn't reboot but stays at the Galaxy S2 screen.

    Everything seemed ok in ODIN but it did not reboot, although i can get into ClockworkMOD.


    As far as i can tell i did follow the instructions given, and i know they are easier but i update my ZTE Blade a fair bit and have encountered the odd bootloop, but with this i am stuck sadly.

    Any help would be appreciated, i did read the guides and it all seemed to flash alright.
  13. ironass

    ironass Well-Known Member

    I'm not familiar with the, "P", variant, so could you give me the details of the original stock kernel that was in ICS firmware, prior to you flashing.
    Bailzebub likes this.
  14. Bailzebub

    Bailzebub Guest

    Damn, i noted that down on my works machine.

    Essentially the firmware ended on the same LP6 characters that the CF kernel i chose did.
  15. ironass

    ironass Well-Known Member

    Try wiping your Dalvik cache in Recovery. Failing that, re-flash, following the Dummies Guide, again.
  16. Bailzebub

    Bailzebub Guest

    Thanks so far.

    Sadly i'm having no luck with it at the moment.

    As it stands the phone model is GT-i9100P, Orange branded and upgraded to ICS via Kies, which all seemed to go ok.

    I've tried the wipes and just still get stuck on the reboot screen with the yellow triangle.


    I'm thinking about installing a stock Orange update now but does this depend on the kernel also? Would like to just start all over again really :)
  17. ironass

    ironass Well-Known Member

    You have two choices as far as I can see...

    1. Flash the stock, Orange, ICS ROM via Odin, from here. This will overwrite your current kernel and install the Orange one.

    2. Since you do not have the exact kernel details to hand, you could try flashing this LP7, CF-Root kernel, here.
  18. Bailzebub

    Bailzebub Guest

    Appreciate this.

    This is actually the first time i've messed a flash/upgrade on a piece of kit for ages.

    I'm genuinely usually careful :eek:


    I will try those methods, i also used a program called Fusdownloader which gave me this information regarding my model on Orange.

    Product Code: GT-I9100LKNORA
    Latest firmware: I9100PBVLP6/I9100PORALP7/I9100PBVLP6/I9100PBVLP6
    Modified: 20/04/2012 22:09:50
    Filename: on Orange.

    Cheers again, hopefully i can sort this :)
  19. ironass

    ironass Well-Known Member

    Go for the LP7 kernel first... what have you got to lose? :D

    He who dares Rodney... he who dares!
    Bailzebub likes this.
  20. Bailzebub

    Bailzebub Guest

    "Play it cool Trig, plaaay it coool".

    Followed your advice there ironass and i can happily say i've now got a fully rooted SGS2 running the latest Andy's mod and Synah (sp?) kernel.

    All backed up and running now, thanks a lot for taking time to help a newcomer :)
  21. ironass

    ironass Well-Known Member


    Nice one Bailzebub!

    I think you might find that the stock ICS, Orange firmware, for the, "P", variant, has an LP7 kernel. That would explain why you could not get it to work before.

    Congratulations! :congrats:
  22. JohnSGS215

    JohnSGS215 Member

    Can someone pls tell me whether this guide is for SGS2 I9100 or I9100G? As I do not want to spoil the expensive phone. I am only new to this. Thanks in advance.
  23. Shotgun84

    Shotgun84 Well-Known Member

  24. JohnSGS215

    JohnSGS215 Member

    Thanks for above. Is there a way i can reset my phone if something goes wrong? will i lose my phone memory when rooting? Other than that, can you also help me find the kernel for my phone, I'm not sure which one is it, my phone kernel version is se.infra@sei-43 #2. Thank you very much.
  25. ironass

    ironass Well-Known Member

    That rather depends on how badly you plan on fouling it up!

    If you want to, you can re-flash your original kernel back again. If you, "brick", your phone, by, say, yanking out the USB cable during the rooting process... that could be a little more involved.

    Taken from post #1.

    Taken from post #1.

    Reading through the thread mentioned above, the, "Lucifr", kernel seems to be the most popular for rooting, see here.

    Since you have the, "G", variant, (judging by the kernel version you have posted), of the Samsung Galaxy S2 this thread should prove very useful and this post in particular, by Shotgun84, describes your kernel and how to root it and can be used in conjunction with this guide.

    I would suggest, strongly, reading the, "G" variant thread, thoroughly and carefully, as this applies directly to your model of handset and is tailored for the, "G", users.

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