Install the latest Samsung USB Drivers on your PC so it can communicate with the phone in Download Mode.
Downloading and installing the official Android 4.1.2 Jelly Bean firmware for the is a common way to restore your device to its original factory state, fix software bugs, or unroot it. This version was a major update that introduced improved stability and features like Multi-Window to the S3 series. Firmware Details for GT-I8190 (Android 4.1.2) s3 mini firmware 4.1 2 download
You will need the Odin3 flashing tool (v3.04 or v3.07 are commonly used for older devices). Install the latest Samsung USB Drivers on your
Before flashing, you must prepare your device to prevent data loss or "bricking" (software failure): fix software bugs