Screenshot_2015-05-24-12-59-22At long, long last I finally worked out how to cure my Navon Mizu M500 Android smartphone of the insufficient storage issues that were bedeviling it. Despite all my past efforts to clean it out, the phone was down to just 1.1MB of internal storage lately. But as of this morning, I’ve freed up around 500MB, and it looks like this solution will stick.

For the benefit of other troubled Android phone users, here is how to do it. Two caveats, though. First, your phone needs to be rooted. Second, I take no responsibility whatsoever for any bricking of your device as a result of this process. I found it out totally ad hoc myself, when I was browsing through the /data directory out of sheer frustration, and I can’t guarantee what will happen if you do it. But it worked for me.

Using a root explorer took – in my case, the Explorer function in the SD Maid system cleaning tool – I browsed to the /data directory, and while going through the sub-directories in search of big and junkable files, I found the /core/ directory. This contained a series of dated zip files titled zcore, each somewhere around 60MB. I haven’t been able to find any reference online as to what these are, but I assume they’re backup logs of some kind. So I started deleting these, one by one.

Now, anything with “core” in its name is obviously something you should touch only with great care. And yes, the phone did start to behave a little oddly at times as I did the deletions. But after a restart and a couple of anxious moments while I waited to see if I’d bricked the device, I got my old phone back, with its old capacity restored.

Now I can install and update apps again, and generally do all I used to do when my phone was freshly formatted. And I can go back and do it again any time the same problem recurs. But like I say, no promises that this will work on any other phone. So far, all seems to be going well. Fingers crossed, though.


  1. Hi, i had some problem with my phone. In /data/core/ many files has name I just delete this files.
    Root access i get in factory mode – when i reboot device press power+volumn up+volumn down after that connect usb cord and login adb shell (android-studio-bundle)
    Now I wait – will be in my phone.

The TeleRead community values your civil and thoughtful comments. We use a cache, so expect a delay. Problems? E-mail