How to get back write access to SD-Card on Android 4.4

[ghisler(Author)]

Here are the instructions to get back write access to your external SD-Card on Android 4.4 with just tempoary root, and without losing your warranty.

Before you begin, you need to check whether this will work on your device or not:
1. Open device settings
2. Open "About your tablet/phone", or "Device information". It's usually the last option of the settings
3. Check the Kernel version: It will only work if the Kernel build date is June 3, 2014 or older.

If it is, follow these steps:
1. Get Towelroot and run it: towelroot.com
Note: You may get a warning about a virus. This is not true, you get this warning because the tool uses an exploit in Android to get root rights.
If Towelroot worked, it will report it. Otherwise your device may reboot, then it failed. There is no danger in using this tool. All it does it put 3 files on your device:
/system/xbin/su
/system/xbin/daemonsu
/system/etc/install-recovery.sh

2. Get and run SDFix:
https://play.google.com/store/apps/details?id=nextapp.sdfix
On my S4 mini, it complained that it failed to copy the data, but it did work. The app modifies the file
/system/etc/permissions/platform.xml

3. Now all we need to do is unroot the phone by removing the above 3 files. I wrote a little tool which does exactly this:
https://plugins.ghisler.com/android/simpleunroot1.apk
The tool is open source.

4. Restart your phone/tablet.

Of course you can also decide to keep root access - in this case, you should install SuperSU - otherwise any app can get root rights without warning the user.

[DimitriJunker]

My Android is from July 23rd 2014, so the solution is not applicable for me. According to Samsung the new API allows Apps to write to the SD-Card, but they need to be updated. I quate (in german)

Google hat mit der Android-Version 4.4.2 die Programmierschnittstelle (API) für den Zugriff auf die SD-Karte geändert. Hat der Entwickler die Anpassung nicht für seine App vorgenommen, bekommen Sie die Fehlermeldung, dass auf die SD-Karte nicht zugegriffen werden kann. Auf der Google Developer Seite selbst sind diese Änderungen veröffentlicht und noch einmal detaillierter beschrieben.

So if this is true Total commander could be updated so that it can write to the sd-card. I tried some other apps, one was able to create new folders on the SD-Card but could not copy files there.
Else nice App as the other Versions I use(d) ( Windows and the old Windows mobile)
Dimitri

[ghisler(Author)]

2DimitriJunker
The beta version DOES support the new API to write to its own private SD-Card directory. When you go to the TC home folder, you can see multiple SD-Card links. The one with R/W in the name is the pointer to the private directory where TC is allowed to write.

Unfortunately there is no API to write anywhere on the external SD-Card.

[DimitriJunker]

So every app gets a dir where it is aloowed to write, but they can read all dirs. This is rediculous. But that's not your mistake. Can a app change the permission for it's directory so that it becomes writable for every app? So could TC create a subdir public under which every app could write and read? The actual TC can't do it, but woul`d it be possible?
Thanks any way
Dimitri

[siealex]

The best variant is to downgrade to Jelly Bean and stay on it forever.

[siealex]

So every app gets a dir where it is aloowed to write

More, this dir is cleaned up every time you delete, update, freeze or reinstall the app.

[ghisler(Author)]

No, actually the best solution is Towelroot with SDFix. If your firmware is too new, downgrade to 4.4.2 and use Towelroot.

[petermad]

I have a HTC One (M8) with Android 4.4.3 KitKat

Under Settings -> About -> Software information -> More -> Kernel version - it shows this info:

3.4.0-ge224610
and@ABM102 #1
SMP PREEMPT

But no info about the build date. any othe idea where to find the build date?

[widmannw]

I have a Samsung TAB S 10.5 (SM-T805) with Android 4.4.2

3.4.39-2085187
dpi@SWDD5908 #1
Mon Jun 30 21:12:29 KST 2014

No write, create and delete acess on extSD (SD-Karte (2))
Towelroot does not work: This phone isn't currently supported

[petermad]

Hmm, I tried running towelroot, and it did run through (no rebooting) and told me that I should now have root access.

But when I then run SDFix it tells me that I don't have root access, and so does TC if I try to enable the "Root functions everywhere" feature.

Afterwards when running simpleunroot1.apk - it just says "This tool is only meant to remove Towelroot!" - so apparantly the towelroot files were not installed.

[ghisler(Author)]

2petermad
4.4.3 is probably too new.

2widmannw
June 30 is too new for Towelroot.

2petermad
Try checking in /system/xbin whether there is a file "su". If yes, it should have worked - try restarting the phone. if not, it failed.

[petermad]

Try checking in /system/xbin whether there is a file "su"

I don't have a su file - I don't see any of the files mentioned in the first post. So even though towelroot says it did succeed, it obviously didn't. Today it did reboot the first time I tried, but not the 4 following tries. Also the first time I saw a system tray message after the reboot, that a recovery had been made by the system after a shutdown.

[franc]

I (my girl-friend) have a CAT B15Q, after installing and running towelroot it says: this phone isn't supported.
Kernel is from 15 May though, but no way to root this phone I read.

What now?

I cannot write even the folder:

/storage/sdcard1/Android/data/com.ghisler.android.TotalCommander

at least this should be possible isnt it?

[ghisler(Author)]

I (my girl-friend) have a CAT B15Q, after installing and running towelroot it says: this phone isn't supported.
Kernel is from 15 May though, but no way to root this phone I read.
What now?

This should work - you can try to use parameters with towelroot:
https://towelroot.com/modstrings.html

I cannot write even the folder:

/storage/sdcard1/Android/data/com.ghisler.android.TotalCommander

at least this should be possible isnt it?

Yes, it should work, unless the phone is configured to not allow any writes at all.

[franc]

...This should work - you can try to use parameters with towelroot:
https://towelroot.com/modstrings.html...

I will try..

To fix, align and method are probably your best bet(4*2=8 values), hit_iov maybe, limit_offset if you are desperate.

I see me yet trying limit_offset
(4*2*2048=16384 values)