Thank you for using Bitnami. I understand that you had an old version of MediaWiki installed at
/Applications/mediawiki-1.26.2-0/, if you copied the files of the new version of MediaWiki 1.31 to the htdocs folder, you could break the entire installation as you are replacing the files of an installed and configured MediaWiki with the non-configured MediaWiki files.
Apart from that, as you noticed the new versions of MediaWiki requires PHP 7.x and your installation used 5.5.x
It's not so simple, you need to migrate the information of your current MediaWiki installation to a new one. We only offer the OS X VM solution for MediaWiki right now, the OS X installer is not available anymore. But please follow these instructions to migrate your installation
- Create a backup of the database of your current installation
mysqldump -u root --databases bitnami_mediawiki -p > mediawikiBackup.sql
- Install it and start the services
- Click on "Open Terminal" and run this command (and don't close the terminal)
sudo mkdir /opt/bitnami/temp
sudo chmod 777 /opt/bitnami/temp
- Copy the .sql file you created in the first step to that temp folder
- Open the terminal again and follow these steps
Let us know if you have any questions.