How to FIX: Error: MySQL shutdown unexpectedly

Important: do not delete the ibdata1 file. You could destroy all your databases.

Steps:

1. Rename folder mysql/data -> mysql/data_old

2. Make a copy of mysql/backup folder and name it as mysql/data

3. Copy all your database folders only from mysql/data_old into mysql/data (except mysql, performance_schema, and phpmyadmin folders)

4. Copy mysql/data_old/ibdata1 file into mysql/data folder

5. Start MySQL from XAMPP control panel

It should resolve the issue.