file permission problems with the /mnt/sdcard2 directory.

[raaaaaymond]

Hi, I'm new here. I've spend hours on the internet trying to search for my problem, but to no avail.

I'm using Sony Tablet S, but I suspect that this problem isn't device-specific. After a recent upgrade to Android 4.0.3, I can no longer modify or delete files from the /mnt/sdcard2 directory, which is where the external SD card slot is mounted. After checking the properties with the ES Explorer, I found that the /mnt/sdcard2 directory does not have write permission, and only has read permission. In contrast, the /mnt/sdcard directory, which is the internal storage, does have the write permission and is working properly. But, when I checked the directory permissions in an app called "Terminal IDE", both /mnt/sdcard and /mnt/sdcard2 directories appear to have the same permission, both 'd---rwxr-x'. So clearly there is a discrepancy between what Terminal IDE thinks a directory's permissions are, and what ES Explorer thinks the permissions are. Why is that?

I have another question. How does one change the directory permissions on Android? If I can do that then maybe /mnt/sdcard2 will start working again.

Thank you very much in advance for your help!

 

[valorian]

Welcome to AF

I'm pretty sure you cannot change permissions on an Android device unless you are rooted.

Hopefully someone more experienced will be able to provide more help.

 

[raaaaaymond]

Thank you Valorian for your reply.

Here is an update. It looks like the problem is that somehow, over the past few days, the group of the directory /mnt/sdcard2 has changed to 1023. If a run command 'id', I get uid=10084 gid=10084 groups=1015,3003. As we can see, I'm not in the group 1023, and that's why I can't write to directory /mnt/sdcard2.

Am I the only person experiencing this problem? It seems to me that this is a pretty dumb problem! Why would Android, or Sony (I don't know) set the permission of the external SD card so that normal users cannot write to it? Is anyone feeling me?

 

[lunatic59]

Have you recently read the external SD card using a card reader adapter? Some of them have a little read-only switch on them that may set a flag on the card.

 

[raaaaaymond]

Thank you Lunatic59. Do you mean a software switch or the hardware switch on the actual SD card? I assure you that the hardware lock is not locked.

I have not recently read the card with another external reader before my device couldn't write to it. I have since tried to read the card on my computer and everything was fine, I had all the permissions I wanted. I have also tried different SD cards. I'm pretty sure that there is nothing wrong with the card.

 

[lunatic59]

I have seen a hardware switch set a software lock on an SD card. One other thing you might check is to make sure the card was unmounted cleanly the last time it was read in the card reader. If you don't normally "eject" the card, you should try putting it in the reader, mount the file system and then unmount it from the USB menu.

 

[miko4inet]

I have same problem on my Sony tablet S after update Android to v4.0.3.
Official support don't give me an any adequate answer. I mean that we have 2 way:
1 - To wait while for Sony will provide official patch, or
2 - Wait for the recipe to get a root permissions from hackers


P.S.
http://forum.xda-developers.com/showpost.php?p=25458857&postcount=55
Here is a way of a solution, BUT you should have root permissions at first

 

[raaaaaymond]

Oh wow Miko4inet, it's a relief to know that I'm not alone with this problem. I have sent Sony a long email explaining this, but I'm not sure whether they'll get back to me on that.

 

[raaaaaymond]

Just for your information, here is (part of) what I received back from Sony Support after contacting them. It was actually quite informative and helpful.

After reading your email, we regret to inform that this issue is due to a limitation in the Android ICS 4 edition which prevents the user from writing on the SD card. An investigation with Google is already in progress and we are looking forward for them to develop a solution to fix this issue as it is affecting all kind of devices that runs on this operating system edition.

So it looks like this is an Android issue and not specific to Sony. If anyone is reading this and have similar problems, I implore you to please write a quick post here, so that this problem can gain some support.

 

[valorian]

I'm surprised to here Sony say this. I'm running ICS on my phone and I can read and write to the SD card fine. Maybe it's an ICS on Sony phones issue?

 

[Viochemist]

I'm just now noticing that I have the same issue with my Sony Tablet S. This actually answers why my backups have stopped working. My other ICS device is a GNex which doesn't have an SD card, so I can't make a comparison. Any news on a solution?

I will note that you CAN use Sony's file transfer app to delete files off the card, just not third party apps it seems.

 

[DrDaveMGP]

I'm just now noticing that I have the same issue with my Sony Tablet S. This actually answers why my Syncs have stopped working. It is the same issue. Have a totally useless 32Gb SDcard now. Was syncing all the cloud boxes Dropbox, Google, Skydrive etc. onto it.

 

[blaqq]

I have a Sony S Tablet I have the same problem. I regret the day I upgraded to 4.0.x. I held back for the longest time, wondering what the advantage was to doing so, till I decided to go ahead, and then this ( For anyone thinking of upgrading from 3.x DO NOT IF YOU VALUE WRITING TO /mnt/sdcard2

 

[vijer]

I know this is an old thread but I imagine this question is going to reappear with the introduction of Kit Kat. I experienced this problem immediately after installing KK.

This solution worked for me.

1. Using a root-enabled file manager, navigate to /system/etc/permissions and make sure you have mounted the file system r/w.
2. Edit platform.xml and find the ACCESS_ALL_EXTERNAL_STORAGE permission.
3. Add an additional group definition for this permission...<group gid="media_rw" />
4. Save the changes to the file.
5. Restart your

 

[lunatic59]

Hello and welcome to Android Forums, vijer.

There is an ongoing discussion about some of the changes with Kit Kat in this thread you might find interesting.