Archived - Mac OS X 10.5: Can't log in to account that has no password
After installing Mac OS X 10.5 Leopard, you may not be able to log in to a user account that has no password, if it was originally used in Mac OS X 10.2.x and migrated to Leopard after installation.
- Start up from your Mac OS X 10.5 Leopard Install DVD.
- From the Utilities menu, choose Reset Password....
- Reset the password for the affected account(s).
Note: Having a user account with no password is not recommended.