To flash root file, first you need to flash recovery img
To create recovery img and to flash root file Follow the below procedure,
1) Download scatter file, Unite_2_4.4.2_Proper root.zip, SP flash tool and mtk driod tools
2) Open SP Flash tool and select scatter file under 'Download' tab.
3) Now go to 'Readback' tab and click on 'Add', then it will adds one entry below.
4) Double click on the entry and then choose the path to store ROM_0 file.
5) Then it will opens another window to enter starting addr and legnth, Enter legnth as '0x03d80000' and click on ok button.
6) Then Click on 'Read Back' and connect phone without battery. Wait till it completes.
7) After completion place the battery and switch on the phone.
8) Enable USB Debugging in the Developer options menu.
9) Extract MTK Droid tool zip (Disable if your antivirus software is deleting the zip file)
10) Open MTK Droid tool, click on 'root, backup and recovery' tab.
11) Now connect your phone, then it will detects it automatically.
12) Click on 'To process file ROM_ from Flash Tool' button.
13) Locate the file you got from read back (Default -'ROM_0').
14) Say yes to make CWM recovery and after completion Get the recovery img from 'backups' folder in 'MtkDroidTools' folder.
15) Your done with recovery img. Now you need to flash it. Before that Disconnect the Phone.
For Flashing Recovery And Rooting it:
1. Open SP flash tool and check the Recovery checkbox under download tab.
2. Double Clicking on Location column of 'Recovery' Row in sp flash tool and select the recovery made by mtk droid tools (Micromax-A190_xxxx_recovery_).
2. Click Download in sp flash tools, remove the battery from phone and connect it to pc.
3. A green circle/download ok will confirm flashing.
4. Copy the root file Unite_2_4.4.2_Proper root..zip into sd card.
5. Insert the battery,sd card and reboot to recovery. Make a Backup.
6. Select install from sd card and select Unite_2_4.4.2_Proper root..zip and say yes to flash.
7. Reboot, Done.