I'm using wordpress3.1; I clicked to install wp-tuner, and got the screen for /install.php, with the message "insufficient requirements; you cannot install because wordpress 3.1 requires MySQL version 4.1.2 or higher. You are running version ." (I am actually running version 5.1.48)
I had to remove the plugin files to be able to use my dashboard at all, as otherwise it always went to the install.php page.
I tried a few times, eg with all my plugins deactivated - same, except sometimes it appeared to install, and then hung only when I clicked 'activate'