Complete guide: How to root, backup, and flash new ROM and kernel on your HTC EVO
IMPORTANT: This complete guide was written for Android 2.2.x (Froyo). To root Android 2.3.x (Gingerbread), please follow this tutorial.
This massive guest tutorial was written by MildlyDisturbed.
When researching rooting your HTC EVO 4G, you've probably run across hundreds of pages of information, all with people running different ROMs and kernels who each have their own opinions on what was the best way to get to where they're at at the time they did it.
Unfortunately, the hours march on and what worked back then doesn't always work now. New software can break old styles of rooting, and by now someone who rooted their EVO 3 months ago may not be able to tell you what will work for you today. It can be a very frustrating experience, especially when forum members respond to your questions with "read this, that, that, this, that, this, and that before you ask a question here." And although it may seem rude and unhelpful, they have that right; you're probably posting in a several-hundred-page thread that already contains the answer to your question in several places.
Rooting is a moving target.
So, for all of you unrooted people out there, here's a long-winded walkthrough of getting to root, backing up (Nandroid), flashing a ROM, and then installing a custom kernel on your HTC EVO. Some of this has already been covered on G&E before, but now it's all in one place.
WARNING: Follow this tutorial at your own risk. Make sure you're OK with anything on your phone disappearing. Sync your contacts, backup what you can, and kiss your Angry Birds save point goodbye (unless you backup with Titanium Backup first).
How to Root
You're going to need a couple of things downloaded to your Windows computer before you root:
- unrevoked3 (as previously mentioned, v3.3 works with the latest EVO software update)
- HBOOT drivers
Now let's get started.
- If it's installed, uninstall HTC Sync; you can re-install it later if you want to.
- Install the HBOOT drivers as per the instructions provided by the unrevoked team.
- Turn on USB debugging on your EVO by tapping Menu -> Settings -> Applications -> Development -> USB debugging. If you skip this step, unrevoked will fail after your phone reboots (failing will cause a window to pop up that said it failed).
- Plug your EVO into your computer and make sure the USB connection is set to charge only.
- Run unrevoked's reflash_package. Once you press OK, you will not have use of your phone for about 5 minutes.
- Step away and go make some coffee. When you come back (and if everything went smoothly), your phone will be rooted.
Congrats! You're rooted. You can stop here if you want, or you can continue reading to see how far down the rabbit hole goes. You shouldn't have lost any data at this point.
How to Make a Nandroid Backup
If you ever need to take your EVO in for service, the backup you create from your freshly rooted phone is the one you'll want to restore. If you decide you hate what your phone has become, you'll restore this or the next one. If something goes wrong when you flash a new ROM, you can go back to the one you backed up. And so on. In other words, a Nandroid backup is very important.
Jenn has already written a tutorial on how to create a Nandroid on your EVO, so go ahead and follow those steps and then come back here when you're done.
Too lazy to click on that link? Fine. Let's go through the steps again here.
But first, download and install ROM Manager (one of G&E's must-have root apps) from the Market.
Open it, ignore it wanting to flash ClockworkMod 3.0.0.x, and scroll down to "All Clockworkmod Recoveries" at the bottom. For the purposes of this tutorial, we're going to install ClockworkMod Recovery 2.5.0.7, as 3.0.0.0 and above don't support one of the features we might need (long story about scripting types you can read about by looking up Edify Scripting if you're interested)
As already outlined in Jenn's Nandroid tutorial, there are two ways to create a Nandroid backup: the easy way and the hard way. We'll start with the hard way because you should gain familiarity with recovery mode.
Hard Way
- Turn your phone off.
- While holding down the volume down button, press and hold the power button until the screen comes on. You're now booting into the Bootloader menu. It will present 4 options that you can't choose yet and you'll see it searching for 3 files (one of these is PC36IMG.zip; if you've left that in the root of the SD card you've got another minute to wait as it runs through checking it. Assuming that's there, choose no you don't want to flash and no you don't want to reboot).
- Select Recovery from the menu. If it just flashes and pops you back to this menu, you'll need to boot your phone back up, go back into ROM Manager, clear the download cache (Menu -> Clear Download Cache), and reinstall ClockworkMod 2.5.0.7.
- You should now be at a black background with orange or green lettering (I'm colorblind so I don't know which one). Choose Backup and Restore > Backup. It will take about 8-10 minutes and back up everything on the internal memory to the SD card. Your backups are located in a newly created ClockworkmodBackupwhatever date folder as 8 or so files. You can move that folder to your computer if you want more space; just move it back to that directory for the backup to show.
- Reboot your EVO from the menu option (reboot phone option).
Easy Way
- Open ROM Manager.
- Tap
Backup Current ROM. - Leave the filename as the date or change it to whatever you want.
How to Flash a Custom ROM
Having root without doing anything with it is useless. The point of root is generally to gain control of your phone. Your next step will be either to choose a custom ROM or a custom kernel. After you check out all the root-only apps that were previously unavailable to you, my suggestion is to change your ROM out next.
The first thing you need to do is download a custom ROM.
For this tutorial, we'll use the All-In-One Sprint Lovers ROM but feel free to use something else. Sprint Lovers is almost identical to what you have now, though, so it's a good place to start. This ROM includes Wireless Tether, 3G wired tether, a bunch of visual tweaks, power down menu enhancements, and all up-to-date Sprint software that is now able to be uninstalled.
If you downloaded a different ROM or the stand-alone version (not the all-in-one) of Sprint Lovers, then you can move the unextracted .zip file to your SD card and easily flash it using ROM Manager (Install ROM from SD Card -> select file > check Backup Existing ROM and Wipe Data and Cache -> OK) or by following Jenn's tutorial on how to flash a .zip on your EVO.
Skip to the next section when you're done.
If you downloaded the All-In-One version, then keep reading.
- Save the downloaded file, which should be called PC36IMG.zip, on your computer. It should be about 200MB or so.
- Open the file with your archive program of choice (I personally suggest WinRar). Whatever software you use should have a Test Archive button. Do this. It may take a few minutes to test every file, but I've had a lot of failures from free download hosts in the past. It is better to waste 10 minutes testing a file than be down for hours later.
- Plug the EVO into your computer, select disk drive mode, and copy the unextracted PC36IMG.zip file to the root of the SD card.
- Make sure you did that Nandroid backup outlined in the previous section; you'll need it if anything goes wrong here. Also make sure that you have a decently charged battery. If you're down to about an hour or so left, charge that thing up. Flashing drains juice, and if you lose power during a flash, things can get ugly. You should not be plugged into the computer while doing this, as some ROMs like to get odd when connected via USB and flashing for the first time.
- Turn the phone off and think about what you're about to do. You will erase everything on your EVO that's not stored on the SD card. Any applications you paid for will be able to be re-downloaded for free after you install the ROM and set up your Gmail association.
- While holding down the volume down button, press and hold the power button until the screen comes on. You will see a menu with 4 or 5 options display for about 3 seconds and then some text will pop up saying it's searching for a couple of files that will not be found and PC36IMG.zip (this is the file you moved to the root directory of your SD card in step 4). The EVO will appear to lock up, but over on the right-hand side you'll see a little horizontal progress bar as the phone for some reason reads through the entire .zip without bothering to test it.
- You'll have the option here to flash, or not flash the update. If you didn't make a Nandroid backup, or a burglar is breaking into your house, or you need a functioning phone in the next 15 minutes choose no. You can do this again later if you want. If you're ready for your new ROM, then choose yes.
- Be patient. It will flash and then either ask you if you want to reboot or just reboot on its own. You will have a very long boot. It will look like it's locked up. This first boot will take about 8-12 minutes. This, in panic time, is 37 minutes. This is a time for you to go outside, grab a drink, sip it down, and not think about the phone for a bit.
- Come back in now. If everything went well, then your EVO's screen is either off or the Android lock screen is showing. Wake/Unlock it, set up your Gmail association, and you're good to go.
- Make another Nandroid backup at this point.
- You can delete the PC36IMG file off your SD card if you want, but I suggest you wait a bit in case something screws up.
How to Flash a Custom Kernel
A kernel is the driving force behind what happens in your EVO. Generally when you want to save on battery life and get better performance, you get a new kernel.
There are a ton of kernels out there. My personal favorite is the Netarchy/Toastmod 4.3.2 cfs-nohavs-nosbc-noUV-universal (no undervolting), but go ahead and use another one if it's compatible with your ROM (Nandroid first!). I like this kernel because it's stable, allows for underclocking (saves battery) or overclocking (makes high-end games operate smoother), uses minimal power when not doing anything, and generally gives me a lot better battery life. Your mileage will vary: your usage patterns, your EVO's hardware version, where the components in your phone were made, etc. will make a difference.
- Download your chosen kernel to your computer, open it with whatever archive program you use, and test the archive (as mentioned in step 3 of the previous section). I really can't stress enough how many corrupted downloads I have seen from free file hosting sites.
- Copy that file to the root of the SD card or anywhere on the card that you'll be able to find easily.
- Reboot into recovery. If you installed the nice Sprint Lovers ROM from the previous section (or one of the many custom ROMs out there that include power options), you can press the power button and then choose reboot -> reboot into recovery. You can also download Quick Boot (another G&E must-have root app) from the Market. Otherwise, power off the phone and hold down the volume down button while pressing the power button until the screen turns on. The familiar bootloader screen will come up and if you still have PC36IMG.zip on your card, you'll be presented with options you don't want like flashing it or rebooting the phone. Choose no to all of them and select Recovery instead.
- Assuming you flashed ClockworkMod Recovery, another menu will pop up shortly. Select Advanced, clear the Dalvik cache, and find the option that says Format/Clear Cache Partition. Do both of these. The only thing you've done at the moment is ensured there is no junk left in a cache partition that might screw with the new kernel. If you rebooted now, it would take a minute longer to recreate the cache parition, but nothing would be changed.
- Now flash the new kernel the way you would flash any other .zip: install zip from sd card -> choose zip from sdcard -> select file -> Yes – Install [name].zip. Flashin g a kernel can take anywhere from 15 seconds to about a minute. If it takes less than that, there's a chance your version of recovery didn't actually flash it.
- After flashing, reboot, walk away, and give it 5-8 minutes to boot.
You should now have a new kernel.
Oh, Crap! Things I've Learned
If something fails at any point after rooting, you can always restore your Nandroid backup by using ROM Manager (Manage and Restore Backups -> select backup file -> Restore) or booting into recovery and selecting backup and restore -> restore -> select backup file.
If your kernel works for a few days and then mysteriously stops, boot into recovery, clear Dalvik cache and format/erase cache partition, then reboot.
Virus? Restore a Nandroid backup.
Got to take your EVO back in for service? Nandroid your current config, move that to your computer, copy your original Nandroid back to the SD card (if it's not already there), restore that, and un-root. Then get service, re-root, move the other file back to the card, and restore it.
Overclocked your phone to infinity and now every time it boots and loads the overclocking software, it locks up? Either restore a Nandroid backup or boot into safe mode by powering off your EVO and powering it back on while holding down the home button until it boots up. Once you're in safe mode, uninstall your overclocker, reboot, reinstall, and for Pete's sake don't set it to start on boot until you're sure that level of overclocking is doable.
This massive guest tutorial was written by MildlyDisturbed.
