This flash file tested by me without any error working well, you can use this flash file when your device hang on logo problem, restarting problem, security lock problem, password lock problem, pattern lock problem etc software related problem and you can use this tutorial without any box and this is free for all who know about software in mobile, impotent for flashing first must check your micro usb cable if not good then you can't flash it so check micro usb cable second check your device battery that is impotent for flashing if your device battery low so stop your device between flash so this is impotent for flash, before you flash save your data like contact, photos, videos etc because this is factory flash file so you can't save after full flash so must remember all are impotent notes.
Download Link
Intex Aqua Eco Firmware Download
hereRequired for flash:
1. Intex Aqua Eco device with good battery charged
2. Intex Aqua Eco tested firmware
3. SD Card with good working
4. Computer or Laptop for Copy firmware only
Procedure:
1. Download tested firmware from above link
2. Extract it desktop or as you like path
3. Open Intex_Aqua_Eco_V015_Indian_SER folder
4. Open Firmware folder
5. Copy all files into SD Card (see below image)
6. Now Insert SD Card into device and insert battery
7. Press and hold Power + Up + Down same time release Power key when vibrate phone keep pressing Volume up or Down key until Android logo
8. Wait until full upgrade when your device full upgrade then device automatically restarting.
9. You are done
Note : If any problem using this tutorial then leave your comment in below comment box