Please create a backup of all script files, especially those in the folders /configuration/ and /template/. During the update process all existing files will be overwritten and all changes in those files will be lost after that.
Please carry out following steps:
Login to the admin area of the script and go to the backup section. Export a backup.
Connect to your web server using an FTP program. Download the whole script directory including all files and folders to your local hard disk. This way you have a backup of all files and database tables in case the update fails and you need to recover deleted files or data.
Upload all files and folders of the new script version to your server into the folder that contains the existing script. Please be aware that all files are now overwritten by the new files. Make sure the file structure appears on the server.
Call the admin area of the script in your browser:
You are now seeing the update screen of the script. Please make sure you have the database access data. You need following four items:
Database user name
You either get those data from your web space control panel or ask your web space provider about them.
Enter the login data of the admin account. Click the button Update. In case the update was successful, the update form will be gone and you will see the admin area.