[Xperia Arc General] vaibhavknockout:
[Guide] All in one 'Namaste guide' to Bootloader unlocking, Rooting, Flashing & more.

So you got an Arc!!!! Congratulations on being an owner of this beauty with brains. It’s a great phone if you know how to make the most of it. Damn!!! That’s the problem. You don’t know what to do. Google led you to XDA Forums and you are lost in this techy - geeky world of Rooting, Modding and Unlocking. DON’T WORRY. Let’s go on an intellectual yet fun guide on WHAT TO DO WHEN YOU OWN A XPERIA ARC.

[Please push thanks and if possible donate to Lollylost100, Chainfire, kistigun, Androxyde, Bin4ry, constin, Blagus and many such genius’s at XDA without whom we may not be able to move even an inch with this guide].

Feel free to ask anything which you think is not clear to you, i'll be there to help. There is a thanks button on your screen waiting to be pressed & You can always donate to help me get a new phone . ;)

Ques -What the hell is a bootloader?

According to Wikipedia – “When a computer (Your smartphone - Arc) is first powered on, it usually does not have an operating system in memory (ROM or RAM). The computer (phone) must execute a relatively small program stored in memory from which the operating system programs and data are loaded into RAM. The small program that starts this sequence of loading into RAM is known as a bootstrap loader, bootstrap or boot loader. This small boot loader program's only job is to load other data and programs which are then executed from RAM.”

Ques – Ok. So what is meant by unlocking the bootloader and why do I need it?

Every Android phone has a bootloader that instructs the operating system kernel to boot normally. But you need to understand one thing here that as Android OS is an open source OS and is available on a variety of different hardware, every manufacturer (Sony Ericsson – SE, in case of xperia arc) has their own version of bootloader specific for the hardware present in it’s environment. A bootloader is usually locked on an Android device because although it’s an open source OS, still the manufacturers (SE) want you to stick to their Android OS version specifically designed for the device. In order to apply this concept, SE lock the bootloader.

If you want to install a Custom ROM, you’d need to have your stock bootloader unlocked. In simple terms Unlocking the bootloader allows you to install custom Firmware on your Android phone. [Source - [URL]http://www.addictivetips.com/[/URL]

Ques – Got it. But what on earth is a firmware and what is meant by installing a custom ROM (or whatever you call it)?

An operating system (OS) is a piece of software which provides environment for various applications (Yes, the ones you download and enjoy from Android market) to run. For instance, Windows 7/Vista/XP or Macintosh or Linux are nothing but OS’s. A firmware/ ROM is a term used for the operating systems designed for phones. A stock/generic firmware/ROM is an OS on your phone which is developed by Sony Ericsson and comes pre-loaded when you got your phone. A custom ROM is a modified firmware where modifications can vary from modifying the speed of firmware or making it look beautiful.

Ques – Ok. So quickly tell me how to unlock my Xperia Arc’s bootloader and install a beautiful Custom ROM.

Not so fast dear. I described a deal about bootloader and benefits of its unlocking but let’s get practical. There are disadvantages of unlocking the Xperia Arc’s bootloader.

1. Important – If you unlock your phone’s bootloader, you MAY void your warranty from Sony Ericsson.

2. You will loose the DRM keys present in your phone. DRM keys are (sort of) licence files which are required in order for SE’s custom developed apps like Track ID to work. In short you will loose Track ID and some other SE based apps.

3. You will not be able to update your phone by SE's official programs (SEUS and/or PC comapnion).

Ques - Ohh!! So this means that I should never unlock the bootloader of my ARC, what a waste of my smarty phone.

Looks like I’d scared you with this voiding the warranty stuff (sometimes I scare myself too, don’t worry...:p). We have so far discussed the disadvantages of unlocking the bootloader, let's look at some of the major advantages -

1. All the updates released by Sony Ericsson will be available to you within a few hours of their release irrespective of your country of purchase or country of usage of the phone.

2. You will be able to root your phone (read the questions below to know more about rooting) much faster than any other method available.

3. Few custom ROMs are in their final stages of testing. By unlocking the bootloader you will be able to run those ROMs on your Xperia Arc.

Ques – Hmm, so this means that once I unlock the bootloader of my Arc, I will never be able to run Track ID or update my phone using SEUS/PC companion.

Well, there is a catch. The catch is that you can Relock your bootloader :cool: anytime you want. All you need to do is to follow these steps –

1. Go to Blagus's post at http://xdaforums.com/showthread.php?t=1134335 to download Xperia_Relock_Bootloader.ftf file.

2. Follow steps 2 to 7 of the question ("I am still not ready to unlock my bootloader. So guide me how to perform rooting on my locked Xperia Arc.") given below to flash the Xperia_Relock_bootloader.ftf file to your phone.

3. You should be on a relocked bootloader. To confirm, try to use repair function in pc companion or SEUS. If these official programs update/repair your phone, then you had successfully relocked your bootloader.

4. Thanks to itskapil for a video guide at [GUIDE] How To Re-lock Xperia Arc Boot Loader.

Ques – Woooo. Thank you for the information. But Vaibhav, if warranty gets void by unlocking the bootloader and we have a method of relocking the bootloader, then why are we worried about this?

You little genius. Look, I agree that you can relock the bootloader and unlock it as many times you want, but you should always keep in mind that –

1. Even if you will certainly revert back to your initially locked state and hence technically you are not voiding the warranty...:D,

2. still, you can’t get your DRM keys to work once they are gone :mad:.

So, in other words, you can relock your bootloader any number of times but you can’t get Track ID to ever work on your phone. So, if you don’t like Track ID or you can live with alternatives (Shazam works like a charm, why bother about Track ID?), unlocking the bootloader is a really good choice.

Ques – Who cares about Track ID or facebook ‘like button’, android market is full of alternatives. Can you please tell me how to unlock bootloader in little detail?

Sure. I will recommend you to follow this lollylost100’s awesome guide. There is a link to step by step video of unlocking the Arc by ItsKapil :D. Make sure you watch that too.

For those who got their phone by a carrier can't unlock their bootloader officially, by the above mentioned method. In that case, just follow any of these two guides -

1. Paid unlocking - Remote unlocking

2. Paid unlocking - Remote unlocking

Ques – Hmmm. Done unlocking the bootloader. But my gut feeling says this is not the end. Isn’t it vaibhavknockout?

Bingo. You are absolutely right. Now, rooting and modding and theming comes in picture. The real fun begins.

Ques – Can you brief me on rooting?

In tech world, you can access any file in two modes –

1. Either as a basic user who can just read the file but is not allowed to change it in any way, or

2. As an administrator/Root who can read, write and execute any file in the OS/firmware.

When you get a fresh copy of any OS (e.g. Windows, Mac, Linux etc.) or a firmware (e.g. Android 2.3.X aka Gingerbread on your phone), the OS treats you as a basic user. Rooting is a procedure which grants you the administrator/superuser/root/su permissions so that you can modify any file inside your Android OS. Afterall you should be the one to decide the ‘flavour’ of your gingerbread.

Ques – So this means that I can change system files by rooting. Big deal. What can I possibly do by changing the system files and can we discuss the disadvantages of rooting (and advantages – if any…:rolleyes:).

Believe me rooting is a big deal. Here are THE things you can do if your phone is rooted –

1. You can remove bloatware. Bloatware are those crappy apps that comes pre – loaded inside your Xperia Arc (e.g. LetsGolf, Whatsapp, Timescape, postcard, playnow etc.) by SE or your carrier which can’t be uninstalled, which usually drains your battery most of the time and which make your phone slower and laggy.

2. You can get any SE official firmware. This means that if someone like me is having an Indian generic firmware and want to install a generic UK firmware, rooting will allow me to do so (totally officially via SEUS or PC companion). This also means that you can debrand your carrier locked phone to use sim free phone.

3. You can customize your statusbar, lockscreen, bootanimation, homescreen etc. if you are rooted.

Ques – Vaibhav I don’t want to unlock the bootloader (just don’t feel like) but I want to perform rooting on my Xperia Arc. Can I do that?

YES. You can do that. To summarize, you can have locked bootloader and still root your phone. The advantages of rooting is that you can mod your phone without worrying about unlocking the bootloader stuff. You can unroot your phone anytime you want. As far as disadvantages are concerned there is none.

Ques – WoW!!! So guide me how to perform rooting on Xperia Arc.

Note – It is always advised to back up your contacts and other data before trying out any of the following steps. Be ready to wipe your phone to get a clean better firmware. I repeat – IT IS ABSOLUTELY SAFE AND ADVANTAGEOUS TO ROOT YOUR PHONE.

There are two modes of rooting Xperia Arc depending upon whether your bootloader is locked or unlocked. Read next few questions for further details.

Ques – I am still not ready to unlock my bootloader. So guide me how to perform rooting on my locked Xperia Arc.

Don’t worry. XDA’s big brains have developed something called a FLASHTOOL. It will help you getting a rooted 2.3.4.

1. Go to Jozinek’s post on [ROM]Generic LT15i (Arc) 4.0.2.A.0.42 (1247-1041) (Android 2.3.4) and follow the link named ‘http://multiupload.com/xxxx’ to download official SE world firmware/ROM. Unzip the file and save the LT15i_4.0.2.A.0.42.ftf file in a folder.

2. Go to Androxyde’s post at http://xdaforums.com/showthread.php?t=920746 and download the latest version (0.4.1.0) of flashtool.

3. Run the autoextractor in a folder.

4. Download LT15.rar file (attached to this post below) and copy "LT15.sin" to "loaders" folder in flashtool. You can skip this step safely.

5. Copy your “LT15i_4.0.2.A.0.42.ftf” in the "firmwares" folder.

6. Run X10Flashtool.exe (as administrator in case you are working on windows 7/Vista).

7. Follow steps in http://www.youtube.com/watch?v=Keo61Zffh5Q to flash the LT15i_4.0.2.A.0.42 firmware on your phone. The video asks you to download firmware and flashtool, keep in mind that you already did that in steps 1-6 above.

8. After flashing, restart phone and check your Android version, you will be on 2.3.4.

9. Now go to ‘settings’, ‘Applications’ and tap ‘Development’. Tap ‘Unknown sources’ and ‘USB debugging’ to tick on them.

10. Connect the phone (in running state) back to the computer in media transfer mode. Flashtool should detect your phone now. Press the root button on top left side of flashtool and wait(just a button tap and you are done) to root your phone on latest 2.3.4 firmware.

11. Similarly, install superuser and busybox via flashtool. The phone should now be running a rooted 2.3.4.

Ques – I have already unlocked the bootloader of my phone. How can I perform rooting on my Xperia Arc?

Congratulations. Now that you have unlocked the bootloader of your phone, you have opened a way for yourself into an awesomely wonderful world of modding your Xperia Arc. Before we move any further, let's review some techy-geeky concepts :cool: -

1. Partitions – Just like the human brain, a computer needs to store data for performing different functions. Again, a computer also has memory, similar to human brain. But unlike the human brain, a computer possesses two different sets of memories. One is relatively permanent and is called as ROM (Read only memory, should not be confused with android ROMs), the other is volatile and is referred to as RAM (Random access memory/ cache memory).

Our Xperia Arc (or any other smartphone for that matter – even iPhone :rolleyes:) also has two memory system. But unlike computers, smartphones have a single physical memory disk, since it is not feasible to have two different physical memory disks in a small portable device like our phone. To provide the two memory architecture, the single physical memory disk is PARTITIONED into two or more virtual disks. This is similar to the fact that although Asia (or any other continent) is a single continuous physical land surface (you need to ignore mountains and rivers ;)), virtual boundaries make different countries. These virtual memory disks are known as partitions.

2. Boot sector/boot partition (“/boot”)– When your phone (Arc) starts, the bootloader (you know what a bootloader is, right. What, you were sleeping!!) needs to start a boot program (known as a kernel) which further guides the rest of the system to start in sequence (the Sony Ericsson text that appears when you start your Arc is what you have as a kernel). This boot program is stored in a memory partition known as boot sector or boot partition.

3. Cache partition (“/cache”)– A cache partition (as discussed above) is a memory disk space which is volatile. This means that it stores programs temporarily onto it, until the program is executed. The moment a program is no longer needed, it is erased from cache and loaded back to a relatively permanent storage called system partition, where it stays (until user decides to erase it).

4. System partition (“/system”)– All the files and applications that are visible to you in your phone (including all the system files like settings, app drawer etc.) are stored on a disk partition known as system partition.

5. Data partition (“/data”)– Did you ever wondered as to why is it that when you save a setting or install an app, it remains as it is even when you turn off the phone? This happens because all of it is saved in the data partition of memory disk.

6. Recovery partition (“/recovery”)– Recovery is another boot program (kernel) that is added by a manufacture (Sony – Ericsson in our case) to perform restoration and damage control if something goes wrong in the system simply by booting into recovery and skipping the normal kernel boot. Recovery program is usually stored in a partition called recovery partition. Developers utilize this partition to boot their own custom recovery kernels to provide us much advanced functionalities like – Backup, Restore and Flashing to name few important ones. To read more about recoveries follow this.

7. Fastboot – Fastboot is a tool which is used to flash, erase, reboot or boot into a particular boot program (kernel). It is also used to unlock the bootloader. It is a part of Android debug bridge (ADB) supplied by google.

You must have downloaded and installed fastboot into a directory/folder when you had unlocked your bootloader. If you have an unlocked bootloader and you don't know how to install fastboot, watch this video by itskapil. You can download fastboot from a link given in lollylost100's guide.

If you are a MAC user and want to install fastboot follow this guide by im_bol2riz.

To root your phone, simply follow the previous question "I am still not ready to unlock my bootloader. So guide me how to perform rooting on my locked Xperia Arc." to root your unlocked ARC (Yes, the one click method is same for unlocked and locked bootloader phones!, beauty of flashtool!).

Alternatively, after you have downloaded and installed fastboot, just follow these steps to root your phone -

1. – Flash any desired stock ROM for Xperia Arc (download 2.3.4 update from link given in "1." of previous question - "I am still not ready to unlock my bootloader. So guide me how to perform rooting on my locked Xperia Arc.") using flashtool (read the question - "I am still not ready to unlock my bootloader. So guide me how to perform rooting on my locked Xperia Arc." to know how to flash a stock ROM using flashtool). This step is optional if you want to root your current stock ROM.

2. – Download attachments below titled recoveryARC.img and RootXperia.zip. Thanks to jlmcr87 and his post. Copy and paste the file recoveryARC.img to the fastboot folder (folder containing fastboot.exe). Also, transfer the file RootXperia.zip 'as it is' to your SD card.

3. - Open the fastboot folder. Right click on the folder background while pressing shift key on windows PC. Click "Open command window here".

4. - A black cmd window will open. Type in the following command - "fastboot.exe boot recoveryARC.img".

5. - Switch off your phone, connect to the USB cable while holding the menu button (rightmost of the three buttons on Arc). A blue led should light up (It is an indicator of entering in fastboot mode).

6. - Let the process run. Look at the cmd window. If it says the process is complete, remove the USB cable.

7. - On your phone, a menu should appear. This is Clockworkmod/ CWM recovery menu (more about this in later questions). Use volume down key to go to 'install zip from SD card' and enter by pressing camera button.

8. - Choose 'RootXperia.zip' where you've stored it on your SD card. Accept the prompt.

9. - Let the process run until it says that it installed the zip.

10. - Go back to the main menu by either pressing back button or entering into '+++Go Back+++'.

11. - Enter 'reboot system now'. When rebooted, you will have a rooted stock firmware.:cool:

Ques – Ok. So I am now rooted. Tell me how to remove bloatware from my phone.

Good. Now you are talking like a pro. Follow these steps to remove bloatware –

1. Download and install Root Explorer from android market. It’s a paid app worth buying.

2. Create backup folder on your memory card - Open Root Explorer, browse to the ‘sdcard’ directory. Press the button at the top so it is ‘Mounted as r/w’ (button will turn to Mount R/O). Create a backup folder on ‘sdcard’ (press menu button and tap “New Folder” icon). Name it anything you want, we have named ours ‘Backup’. This is the folder that we will move the unwanted apps to. By moving it to the memory card, the Android OS will not see them. The backup means that should anything go wrong you can easily move them back.

3. Go to the app directory - Using Root Explorer, browse to the app directory ‘system/app’. Here you will find a list of all of the apps installed, including all those unwanted ones too. The settings button brings up an option for ‘Multi-select’. This will be used to easily move multiple files.

4. Select apps to remove - The next job is to select which apps you want to remove. Go to Flo95's post [Tutorial] Remove Junk Apps + List (4.0.A.2.368, 4.0.1.A.0.283 & 4.0.2.A.0.42) and find the list of apps which are junk as per your phone's firmware version. You can also follow constin’s post at http://xdaforums.com/showthread.php?t=1089470 and look under section "Safe to remove" for a list of apps which are safe to remove from xperia Arc.

5. Click on the settings button and hit ‘Multi-select’. Select all the apps listed under safe to remove files and then press ‘Move’.

6. Move unwanted apps to backup directory - Now using Root Explorer, browse to your backup folder on your memory card. Make sure the setting at the top is ‘Mounted as r/w’. Then click ‘Paste’. All of the chosen files will then be moved from ‘system/app’ to your memory card.

7. ENJOY YOUR EXTENDED BATTERY LIFE AND FASTER ARC!!!!

Ques – I am loving it…:cool:…ok, guide me on what are the official SE firmwares and how can I change from one firmware to another?

Note - By following the procedure mentioned below, you can easily debrand your carrier sim locked phone, which means that you will remove any carrier logo, bloatware and other carrier imposed stuff (Except of course, the sim lock).

Well, SE releases its firmwares in different countries with slight differences in number of bloatwares. The one we used for rooting guide (in above mentioned question) is a global world firmware. For instance, for the Android 2.3.3 firmwares the UK o2 firmware is believed to contain least amount of bloatwares and is believed to be the fastest.

As mentioned in an earlier question on rooting, you can search for official firmwares in the XDA forums on Xperia Arc in the ROM.ftf format and flash them directly using Flashtool. A good place to start out is [INDEX]: Arc & Neo - full firmware guide! by Ambroos. Choose wisely.;)

If you don’t get your desired firmware, there is also a roundabout to this method for phone’s with locked bootloaders. Using Root Explorer (mentioned in previous question on removing bloatware), follow these steps –

1. Go to kistigun’s post at http://xdaforums.com/showthread.php?t=1082368 and select your desired customization number (e.g. I chose United Kingdom Generic 1247-1073).

2. Open root explorer and go to \system and open the build.prop file in the text editor and change the following three lines:

*ro.product.name=LT15i_XXXX-XXXX

*ro.build.fingerprint=SEMC/LT15i_XXXX-XXXX/

*ro.semc.version.cust=XXXX-XXXX

Change the XXXX-XXXX into the customization number of your desired firmware (1247-1073 for my UK generic selection).

3. Press the menu button and save & exit. Reboot the phone.

4. If you are using pc companion, run it & on your computer and go to:

For windows XP users- C:\Documents and Settings\All Users\Application Data\Sony Ericsson\Update Engine\db\13740270\

Or For windows 7 users - C:\ProgramData\Sony Ericsson\Update Engine\db\13740270

5. And delete the blob_fs folder.

6. If you’re using SEUS, run it & on your computer go to:

C:\Program Files (x86)\Sony Ericsson\Update Service\db\13740270\

7. And delete the blob_fs folder.

8. Shut down your phone. Use SEUS for update or use the repair function in pc companion (You know how to use pc companion). Reboot and enjoy your new firmware.

[Source - [GUIDE]Easy way to brand/debrand or change firmware]

Ques – Hey, you said that if I unlock my bootloader, I would be able to try out different ROMs and stuff available for my Arc? How to do that?

Hold that for a minute. Let us first discuss some basic questions –

1. What is meant by flashing a kernel and recovery? – As previously explained, a kernel is a boot program that calls the rest of the system files in sequence when the phone starts. By default, when your phone starts, your bootloader looks for this program in boot partition. In a special case, bootloader can call a different special kernel known as recovery stored at a different place called recovery partition.

2. What the hell on earth is Clockworkmod? – Also known as clockwork and CWM, Clockworkmod recovery is one of the most widely used custom Android recoveries that is available for most mainstream Android devices (including our Xperia Arc). It allows you to perform several advanced recovery, restoration, installation and maintenance operations on your Android device that aren’t possible with the stock recovery. ClockworkMod recovery has been developed by Koushik Dutta (also known as Koush) – the same guy who brought us the Android ROM Manager (I am proud to be an Indian :cool:).

3. What is Cyanogenmod? – Also known as CM, Cyanogenmod is an aftermarket modification of android OS which includes all the basic functionalities of android (as released by Google) with many added functionalities like inbuilt theme chooser. Current release of Cyanogenmod is CM7 based on android 2.3.5.

4. What is FreeXperia? – Cyanogenmod is not available for all the android devices but a few. The Xperia range of handsets by Sony Ericsson is not supported officially by CM. FreeXperia or FXP in short is a joint venture started by a handful of genuises at XDA to provide CM7 to our Xperia devices.

5. What is meant by overclocking? – CPU of a computer or a smartphone processes a huge amount of information at very high rates. The rate of processing of information (speed of a computer or snappiness of a smartphone) is governed by its clock frequency. We all know that hardwares are fabricated with a maximum limit and a safe limit. Overclocking is to shoot up from a safer limit (clock frequency of CPU) to hardware's external maximum limit. It gives you faster hardware but mostly working more than it is designed to work, hence heating and damage risks. I personally don't like the idea of pushing hardwares too much.

6. What is this Doomkernel? – Doomkernel is a supersmart kernel which is designed for our Xperia Arc by doomlord (he is a member of XDA ;)). It has a lot of functionalities over stock kernel such as CWM recovery, overclocking, voltage change and many more.

Continued in third post