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Important Messages
You can edit the Important Messages shown on the Login screen very easily: As admin, just edit the records of type System News which are stored in the root folder.
20-02-16
Welcome to TYPO3
Explore the different roles. Login with one of the following usernames and the password that you choose during the installation routine:
admin = user with full access to the system
simple_editor = very limited access, ideal for basic editing
advanced_editor = more power, but still limited to exactly what an editor is supposed to do