Unlike a CMS like WordPress where multiple users frequently have full Administrator privileges, Drupal is set by default to only allow one Admin (Super User). Other users in Drupal may be assigned to Authenticated roles to publish on the site, but their options will be extremely limited. For example, Authenticated roles lack the basic capability to make changes to the site layout.
This can be a problem when the web developer with Admin privileges goes on vacation or leaves the project completely. If the owner of the site has hired a developer, the developer will likely be assigned the role of Administrator and the owner will be given the lesser Authenticated role. What happens then when the site owner wants to work with a different web developer? Most likely, they will give the new developer their Authenticated username and password to work with. This will not give the new developer the authorization to make needed changes or even to give themselves the needed Administrator privileges within the Drupal interface.
An easy way to change this is to sign in to the database through myPHP. Once in, select Browse on the “users” table. There you will see a list of users. Select the user with the “uid” of 1 and edit that to a different number or delete the user from the database. Next, select the user you would like to grant full Administrator privileges to and edit their “uid” to 1. Refresh the Drupal page and you should now see access to the full Administrator panel.