SharePoint Error: Access Denied when Creating a Publishing Page

Problem

An edge case, this error or phantom error will occur seemingly out of nowhere when a user attempts to create a page on a publishing site.

Explanation

Much like a report writer queries your print driver for margin and layout settings, SharePoint pulls up the master page template to layout a new publishing information. There’s a good chance you’ve removed and re-created your own “Portal Contributor” or “Portal Viewers” group. Be careful not to delete out-of-the-box SharePoint groups without thorough testing, better yet, rename the group instead of deleting it.

Solution

Grant read permissions to the master page library on the root of your portal (site collection).