|"I am the user, the owner of the computer and therefore I assume, the administrator."|
You would have administrator privileges (rights) by default for your user, in that case.
You can check for what user has what rights in Control Panel - User Accounts .
Is there more than one person using your computer - more than one named Windows user, besides you (and the Administrator user when you boot into Safe mode) in Windows?
If there is more than one user, as I said above, sometimes when software is installed you are asked whether you want - only the user who installed the software to be able to use the software, or - you want all users to be able to use the software; in the former case, only the user that installed the software can use it, regardless of whether other users have administrator privileges.
If some other user installed the software, Nero may have to be Un-installed in Add or Remove Programs in that user's profile, then, if you want to use Nero yourself, it MAY be possible to install it such that all users can use it.
If there are no other users, then someone may have tried to install the Nero software in your user profile but it didn't install properly. Is that possible?
Have you changed which WMP version you have installed?
Which WMP version do you have?
On a computer I have with XP with SP3 updates installed, WMP is version 9.x by default, and there is no listing for Windows Media Player in Add or Remove Programs in Control Panel.
If the WMP version was updated, there would probably be a listing for Windows Media Player in Add or Remove Programs in Control Panel.
"I did not load the Nero program and have no idea where it came from but assumed that good old Microsoft had sent it with an automatic update."
Nero MAY have been included in a non-default newer version of WMP if you (or someone else who uses the computer) deliberately upgraded the WMP version yourself, but otherwise, it would NOT be installed via an automatic update.
As a last resort. you could
- go to the Microsoft site and search for this in the search box upper right:
Windows Installer Cleanup Utility
Download it, install it, run it.
Delete any entry in the resulting list for Nero.
That MAY cure your problem, BUT you MAY have to install WMP again -
Un-install it first if it's a newer version listed in Add or Remove Programs,
- or if it isn't listed there go to Add or Remove Programs, Add / Remove Windows Components - click on the box beside WMP to remove the checkmark, click on Next. etc.,
(this MAY require that you have and insert the XP CD)
go to Add or Remove Programs, Add / Remove Windows Components - click on the box beside WMP to insert the checkmark, click on Next. etc.
or install a newer version of it.
WMP versions are available on the Microsoft web site.