问题
Your configuration file or directory is not writable or there was a problem creating the configuration file. You will have to upload the following code by hand. Click in the text area to highlight all of the code and then paste into a new text file. Name this file 'configuration.php' and upload it to your site root folder.
回答1:
The user that is running the Joomla php files (i.e. the user that runs your web server), does not have write access to the folder that is currently hosting the Joomla site. This means that the installation process can't automatically create the file.
Options are:
1.)You need to change the permissions on the folder so that your webserver can create the file. I suggest you change them back afterwards.
2.) Create the confguration.php file yourself, and place it into the folder where Joomla is being hosted from.
来源：https://stackoverflow.com/questions/16080877/installing-joomla-3-error-your-configuration-file-or-directory-is-not-writable