Now let's start... Please pay attention and read carefully before proceeding... I may not be chanced to explain to anyone after posting this. Got a lot to do at my desk o... Ehn Ehn!
Now, you must be ROOTED in order to view the secret "evil" files taking up space
Public Disclaimer: I shall not be held responsible for any damaged/bricked phones after proceeding with the process below. Reading this post means you have agreed to handle your devices at your own will.
Here we go:
The files in "Internal Storage" cannot be browsed using a normal file browser because inherently Android states that files in this storage be and remain "private".
There must be something inside that is roughly taking up all that space...
1. Root your phone. (Kindly search other threads for instructions on how to root your phone. I hear framaroot is the trending root app for most Android phones at the moment)
2. Download the Root Browser app from here or the google playstore: https://play.google.com/store/apps/details?id=com.jrummy.root.browserfree&hl=en
3. Reboot your phone
4. Open the newly installed Root Browser app, a pop up might come stating if you want to give the app root permission. Don't waste time in Granting it.
5. Locate or scroll to /data/ and delete the folder "log" (on my A+, the folder was labelled as "log_other_mode"
Note that if you are not sure of which folder contains the log files meant for deletion, kindly copy the folder and paste it in another destination where you can easily find it without hassle. So it will act as a backup in case you delete the wrong files and mess up your phone unintentionally.
6. Now go and check the storage you have left. (It should be as free as the 3rd Mainland Bridge during an early morning sanitation)
One of the screenshots below shows the contents of the 'log' folder and then later my storage space after deleting the log files.