the user account named Administrator as it is the DEFAULT administrator account created upon installation of the OS. It is protected and that is why you can't delete it and while all things are actually possible I will tell you that a successful deletion of the Account creates an IMMEDIATE requirement for a fresh installation of the OS.
Now, since you haven't bothered mentioning the EXACT OS and Service Pack level telling you about why you are having problems regarding Netware and Logon Screen will have to await your input.
On my laptop, theres an adminstrator account that I cannot delete. Also, when I try to make the logon screen the welcome screen, it wont let me. It says NetWare must be uninstalled, and I have nothing installed named that. Can anyone help me?

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