When MySQL in the XAMPP control panel doesn't start up with an error

Backup the data folder from the MYSQL folder in the XAMPP folder (or on the desktop for now).

Rename the backup folder in the MYSQL folder to data

Save the wordpress related folders and ibdata1 from the data folder you just backed up to the new data file
Restart the XAMPP control panel again
*This error often happens when you forget to Stop and Quit the control panel during shutdown