After I reset my device, I got a message “unfortunately android.process.media has stopped “.
The problem arise from two apps:
1. Media storage
2. Download Manager

Troubleshooting steps:

⦁ Disable google synchronization (i.e. google sync)

For doing so, go to setting > Account > Google > Untick of all the boxes

⦁ Clear data and disable Media Storage

For doing so, go to setting >Application manager>All Apps > Find
the Media Storage > Clear data > Disable

⦁ Clear data and disable Download Manager

For doing so, go to setting >Application manager>All Apps > Find the Download Manager > Clear data > Disable

⦁ Power off your device and turn it back on.

Now such message will not pop up again.

Note: After you turn it back ON, Enable those disabled apps (Media storage data, download manager and Enable google sync by ticking all those options followed on Step i.)