Revive Adserver Installation Fails: Warnings about a missing file "autoload.php" are shown.

A troubleshooting guide to help when Revive Adserver won't install with warnings about being unable to include a file called "autoload.php".

Symptoms

During a new installation of Revive Adserver, Revive Adserver gives errors similar to the following:

Warning: include(/your/path/to/revive-adserver/lib/vendor/autoload.php): failed to open stream:
No such file or directory in /your/path/to/revive-adserver/init.php on line 61

Warning: include(): Failed opening '/your/path/to/revive-adserver/lib/vendor/autoload.php' for
inclusion (include_path='/your/path/to/revive-adserver/lib/pear:/your/path/to/revive-adserver/lib:.:')
in /your/path/to/revive-adserver/init.php on line 61

Troubleshooting Process

You are performing an installation of Revive Adserver from code that has been checked out of the GitHub repository, rather than installing Revive Adserver from an official release package.

1. If you are simply intending to install Revive Adserver, then stop. To facilitate better performance, the source code for Revive Adserver is modified & packaged as part of the release process; as a result, the code as stored in GitHub is not intended for use in normal installations. Accordingly, you must download an official release package, rather than using the code from GitHub. 
2. Alternatively, if you are intending to perform development of Revive Adserver, then follow the Setting Up a Development Environment instructions.