How to update mysql version in xampp (error with innodb_additional_mem_pool_size)

Simply remove this line from my.ini:

    innodb_additional_mem_pool_size = 2M

It was "deprecated in MySQL 5.6.3, are removed in MySQL 5.7.4."

(If my notes are correct, it has been "unused" since 4.1.0!)

What I did and saved my life:

1. Rename xampp/mysql/data to xampp/mysql/anyname_data (or any name of your choice)

2. Create a new folder and name it > data in xampp/mysql

3. Copy all your xampp/mysql/backup files and folder to newly created xampp/mysql/data folder

4. Now which previous database you want to work with copy that folder from xampp/mysql/anyname_data to newly created xampp/mysql/data folder

5. Restart Xampp with or without "run as administrator"

Amazingly! your database is intact in phpmyadmin.

Thank you very much!

To Upgrade MySql included in XAMPP (I did it on a Windows system):

1. Rename your Mysql directory to some other name.
2. Download the .msi file from the MariaDB link https://downloads.mariadb.org/.
3. Run .msi. Change the install directory to your Mysql location under XAMPP.
4. After completion, copy the old my.ini from the original mysql/bin directory to your new mysql/bin directory.
5. You should be able to start Mysql from the XAMPP control panel.

I found the solution here http://www.mynotebucket.com/update-mysql-under-xmpp/