Take the 2-minute tour ×
Android Enthusiasts Stack Exchange is a question and answer site for enthusiasts and power users of the Android operating system. It's 100% free, no registration required.

I am trying to encrypt my android device (Samsung S3, Modified 4.1.2). I have set a password and made sure my device is plugged in and charged over 80%.

When I select the encryption option, the screen shows a wired-diagram of an Android figure and then restarts after about 10s. There are no errors and I can still use my device, but it clearly has not been encrypted.

I've retried multiple times with the same results. Can anyone help?


EDIT (possible explanation)... My device is currently encrypting. I decided to try with my SIM card removed. I had a SIM lock setup, so I'm wondering if that was interrupting the encryption when the phone restarted. Although I am curious, I am not going to go as far as unencrypting, removing the SIM lock and trying again, so I can't be certain that was the cause.

share|improve this question
Is it plugged into a PC, or into a wall charger? I had a similar issue (with 4.2, I think) and found that encryption failed as you describe when plugged into a PC, but worked with a wall charger. Please let me know if this solves your problem - if so I shall add it as a full answer. –  Simon W Nov 4 '13 at 21:57
I tried both multiple times, but no luck. Thanks. –  doc Nov 5 '13 at 10:12
@Flyto Thanks, that solved the issue for me. Failed silently when plugged into my USB hub (even though it's a fast charge port with no USB connection) but worked with the stock charger. If you added this as an answer, I'd vote for it. –  Ben Challenor Mar 24 '14 at 17:04
@BenChallenor done - thank you :-) –  Simon W Mar 24 '14 at 20:21

7 Answers 7

There was a similar issue in Android 4.2 whereby encryption failed as described if the phone was plugged into a computer's USB port, but worked if plugged into a charger. I don't know when this bug first appeared or whether it has been fixed in a more recent version, but it's worth trying a plain charger.

share|improve this answer

Had this issue also. Solved it by switching of WiFi on the device. I am on a Samsung Galaxy S4 with Android 4.3

Hope this helps solve your issue.


share|improve this answer
off course the wifi only had to be off for the encryption, after that I had it turned on again –  user44533 Nov 4 '13 at 19:32
This does not provide an answer to the question. To critique or request clarification from an author, leave a comment below their post - you can always comment on your own posts, and once you have sufficient reputation you will be able to comment on any post. –  t0mm13b Nov 4 '13 at 21:05
@t0mm13b, how do you know this doesn't answer the question? It sounds far-fetched, but I could possibly imagine a situation where wifi would need to be off for security reasons, so perhaps this is a real answer. –  Stephen Schrauger Nov 4 '13 at 21:16
@StephenSchrauger this feels like more of a comment rather than an answer - it starts with "Had this issue also", more of a "Me too I had this problem"... –  t0mm13b Nov 4 '13 at 21:18
To be fair, user44533 has 1 rep - so they can't comment on other peoples' posts, and are thus only able to help by leaving an answer. I remember this frustration myself ;-) –  Simon W Nov 4 '13 at 22:14

I had the same problem. Daj's advice was the solution. I downloaded a memory management app and killed every non-stock process I could find. I used Titanium Backup to Freeze apps that kept restarting. Then I attempted encryption and it did a quick boot and then began the encryption process. This is the final solution.

share|improve this answer
What memory management app did you use? Could you edit that into your answer? –  geffchang Feb 20 '14 at 4:54

I was able to encrypt my Nexus 4 after removing lot of data from the device. With about 4 GB of free memory (half of my total 8 GB) the encryption was successful.

share|improve this answer

I was having this problem with a Nexus 5 running Kitkat. Bizarrely, after multiple attempts at running the encryption in safe mode, with/without wall power, and with/without USB power, the solution for my particular issue appeared to be simply rotating my device so that it switched to the landscape screen orientation. Running the encryption process in this orientation worked first time.

share|improve this answer

Ive been able to complete the encryption process. In used a memory management app to kill everything but min requirements. Than it worked. Hope this helps

share|improve this answer

Solution that will work 100% of the time, without deleting data, killing android processed, etc.

According to the source of cryptfs.h (http://code.metager.de/source/xref/CyanogenMod/android/system/vold/cryptfs.h) it is necessary to have 16 Kb of empty space on you FS to perform encryption. Plus the 32 byte of padding and 16 bytes for the salt and however many bytes your encryption password takes up... I just leave 32 Mb to make sure, tried with lesser amounts and android does not like.

Detailed instruction on how to do that can be found here (http://forum.cyanogenmod.org/topic/82292-cm102-encryption-does-not-start-stuck-at-splash-screen/) but basically you must issue a few commands from adb. For my 12 Gb tablet the commands are as follows:

adb reboot recovery
adb shell
~# cat /proc/partitions
(look for where /data is mounted, take the size and subtract 32768)
~# mke2fs -T ext4 -L data /dev/block/mmcblk0p12 12488704
(be aware that this will erase your data)

Now install your ROM and apps as you normally would...

Then when you are ready to encrypt boot into safe mode by long pressing the power button until the shutdown menu comes up and then long pressing the reboot button and a confirmation of booting into safe mode will come up, say yes and you will be rebooted into safe mode.

Once in safe mode, go to settings and encrypt your tablet. Could also do with adb like this:

adb root
adb shell
~# vdc cryptfs enablecrypto inplace MyEncryptionPassword

Please mark this post as the answer if it helped you. Thanks!

share|improve this answer
You first say that it works without deleting data, but after mke2fs you say it will. Which is it? –  onik Aug 28 '14 at 12:51

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.