We put the necessary firmware in the zip-archive on the SD-card.
Download the phone to TWRP recovery (turn off the phone - the screen goes off - when you turn off completely - give a vibration signal, turn on - press and hold the Power and then Volume + and hold both buttons until the blue wallpaper with the word TWRP)
Save the current firmware - the "Backup" item - select ALL partitions (Boot, Cache, Data, Recovery, Android Secure, System, Nvram, Uboot), to save space - Enable compression. To speed up backup - Skip MD5 generation during backup. Tap on the Storage strip - select the sdcard if not previously selected. Via Set Backup Name you can specify a name for the backup. Swipe to the right along the "Swipe to Back Up" strip to start the process - the "Backing Up System" window appears.
When saving is finished - click the arrow back 2 times to exit to the main menu.
We do Wipe-s (data cleansing before rolling in new firmware). Through the menu "Wipe ->Advanced Wipe "select items: Dalvik Cache, Cache, Data, emmc (*), Android Secure, System.
Running wipe also through swipe on the words "Swipe to ..."
After wipes (they MUST be done!) - go to the Install main menu item - select the file with the firmware in the zip-archive, the "Zip file signature verification" checkbox is NOT STACKED. Swipe to Confirm Flash. We are waiting for the firmware to finish and click Reboot - System.


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To install the mods on the firmware, we always first save the current firmware (DO NOT LAZY!), Then use the "Advanced Wipe" menu to make wipes only Cache and Dalvik Cache and through the Install menu we also select the zip file and flash it.

(*) emmc - built-in phone flash drive, if you store something important there, then you can not do wipe.

Thank you roxalex

Navigate the menu using the volume buttons, select (confirm) with the power button, return to the previous menu with the back button)

1. Download the necessary firmware and drop it into the root of the memory card
2. Go to CWM Recovery (On the phone off, hold down the volume + and on keys)
3. We select Wipe data / Factory reset, Wipe cache partition, advanced-wipe dalvickcache (This will delete all your data in the phone’s memory)
4. Go to Mounts and storage and do the format / system
5. Choose install zip from sdcard ->Choose zip from sdcard (Chose zip from external sdcard)
6. Choose archive, wait until installation is complete
7.Reboot system now and wait for the phone to turn on, usually after flashing the phone loads longer than usual, so do not get scared and wait patiently

If for any reason you received a “brick” - as a result of unsuccessful firmware, turned off the lights during the firmware or just unsuccessful experiments, then just flashing the official firmware through the Smart Phone Flash Tool and rejoice

Required:
1. Software:

Operating system: Windows XP, Vista, 7, 8
USB drivers for Explay Fresh
Smart Phone Flash Tool Loader
Firmware for Smart Phone Flash Tool


2. Equipment

Apparatus
Usb cable
Charged battery (at least 50%)


The course of action:

Install drivers for your OS version - x86 (32-bit) or x64 (64-bit).
Turn off the phone and remove the battery (if you can not flash the phone without a battery, insert it back and try with it).
Run the Smart Phone Flash Tool (Flash_tool.exe).
Find Scatter-loading and select the file MT6582_Android_scatter_emmc.txt (in the folder with the firmware).

Press the Download button and connect the phone to the computer via the USB cable.
Attention!! Never press the "Format" button in the Smart Phone Flash Tool! As a result, you will get a brick, the firmware of the communication module will fly off, IMEI and network calibration will fly off, and the recovery process will be quite time consuming.
We are waiting for the phone to be determined by the program and the firmware process will begin.
When the firmware completes successfully, a green circle appears on the screen.
We take out the cable from the computer
We insert the battery into the phone if it was stitched without it.
Start the phone.