- Install old version of MariaDB (e.g. 10.6.5) in directory "C:\Program Files\MariaDB\"
- Try to install new version of MariaDB (e.g. 10.7.1) in the same directory ("C:\Program Files\MariaDB\")
The installer will warn you that the directory is not empty, or will not allow you to install a new version in this directory at all
The new version is installed in the specified directory, Windows considers that there are two versions in this directory.