Hi wb2001,
Try the below steps to delete the old entries in the event viewer.
a) Open Event Viewer by clicking the Start button, clicking Control Panel, clicking System and Maintenance, clickingAdministrative Tools, and then double-clicking Event Viewer. If you are prompted for an administrator password or confirmation, type the password or provide confirmation.
b) In the Navigation pane, Click on the category for which you want to clear the entries
c) To delete logs, click Clear Log in the Actions pane.
Note: You will not be able to delete individual entry.
Monitor attempts to access and change settings on your computer
Hope this helps!
Halima S - Microsoft Support.
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