1] A fully-rooted android device.
2] Root Browser.
MAKE A NANDROID BACKUP!!!
Here are the steps:
1] First of all keep in mind that this will work only if the phone is rooted. So if you are not, go ahead and search google on how to root your device.
2] Download and open Root Browser (any). Go to system/etc and find the file 'vold.fstab'. Make a backup of that file and save a copy of it somewhere ( for restoring it if anything goes wrong ).
3] Open that file as a text file.
4] Find these lines: (the may vary from device to device. This is for canvas series. May be same for others like sony, etc.)
dev_mount sdcard /storage/sdcard0 emmc@fat /devices/platform/goldfish_mmc.0 /devices/platform/mtk-msdc.0/mmc_host dev_mount sdcard2 /storage/sdcard1 auto /devices/platform/goldfish_mmc.1 /devices/platform/mtk-msdc.1/mmc_host
6] Do the same with next line. Replace sdcard1 with sdcard0. (vice versa)
7] Save the file and reboot.
I have tested this on my Micromax Canvas Juice, Xperia L and Xperia ZR. If it works with your device please comment below.
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