* A working Tecno phone of the same model
* Download Preloader.bin for Your Tecno phone or keep reading to learn how to extract it
* Download PdaNet
* Download MTK Droid tools
* Download SP Flash Tool
* USB Cord
* Important! Put aside any procedure you think you know because it obviously has not helped.
* Enable USB debugging on the good Tecno phone (Settings > Developer) then connect it to PC
* Install PdaNet on the PC with the USB debugging enabled working Tecno phone still connected
* At the end of PdaNet installation, you should get a "drivers successfully installed" message
* Launch MTK droid tools still with the working Tecno phone connected to PC
* MTK droid tools should detect and display the phones details by the left along with a yellow box at the bottom
* Click ROOT at the bottom of MTK and select Yes/OK if prompted on PC and Grant if prompted on phone
* A progress bar should load at the bottom shortly after which the yellow box should become green
* Click on the root,backup,recovery tab at the top
* Click Backup (MTK should keep writing some things by the right hand side during backup) and wait till backup is complete
* If you get a prompt to pack backup, select No.
* Once backup is complete, don't close MTK droid tools
* Go to the MTK droid tools folder > Backups > Folder named after the phone's model e.g Tecno_m3_backup.... and take note of this folder as the 'Backup folder' because we'll be referring to it soon
* Go back to MTK droid tools and click 'To prepare blocks for Flash Tool'
* A window will open, in this window, navigate to the Backup folder (mentioned above) and select the md5 file
* MTK will start copying some items (check the right hand side) so wait till copying is complete
* If you get an error like "Preparation of files for FlashTool is impossible, file isn't found" then remove all scatter files in the backup folder except one and rename this last one to MT65??_Android_scatter ( where "??" represents the number for your phone model e.g MT6572_Android_scatter)
* Once copying is complete, open the Backup folder and you should see a folder named "!Files to flash"
* Open the "!Files to flash" folder and you should see a file named "preloader.bin" (right-click on the file and select properties to confirm) and it might have a VLC or any other media player icon
* Now that you have the correct preloader file (please forget any other one you think you have), disconnect the working Tecno phone
* Its now time to flash the preloader.bin file to the bricked Tecno phone using SP Flash Tool (see How to use SP Flash Tool)
* Using SP Flash Tool, flash the preloader.bin first.
* If flashing was successful then your phone should be able to vibrate when you press the power button or boot if the correct files are present on your phone; else, flash other necessary files to make the phone boot up and start working normally again.
Source: How to fix a totally dead Tecno phone; wont come on, charge or show any sign of life