Hi All Don't know what I missed, but everything appeared to run right from the command line. I was trying to install subpagelist v1.0. I installed composer in the ExtensionInstaller v2.2 directory per directions. Ran php composer.phar after I created the json file. Output threw everything into the Extension Installer directory as follows. Which I don't think is what was supposed to happen. ExtensionInstaller/ -extensions/ ---SubPageList/ ---Validator/ -vendor/ Anyway, looking at - if ( is_readable( __DIR__ . '../../vendor/autoload.php' ) ) { include_once( __DIR__ . '../../vendor/autoload.php' ); } So changing it to - if ( is_readable( __DIR__ . '/vendor/autoload.php' ) ) { include_once( __DIR__ . '/vendor/autoload.php' ); } worked for me. At far as I can tell it seems to work, Special:Version shows SubPageList and Validator, and the extension SubPageList is working. Going back and looking at v2.0, I see my change was the original autoload.php. ??? Are the instructions correct, for 1.22 only, or is v2.0 for 1.21? Should make a note of it on instructions. Thanks Tom Tom