Hi Wascar,
Thanks for your question.
This event is generated when a logon request fails. It is generated on the computer where access was attempted.
The core issue for the is probably that Network and Sharing Center wants to know whether the guest account is enabled for network access. Please refer to the following link to see detailed,
https://social.technet.microsoft.com/Forums/en-US/a2ae4591-f6e9-4177-8985-f47cdced3dca/event-id-4625-null-sid-guest-account-currently-disabled?forum=winserverNAP
Highly appreciate your effort and time. If you have any questions and concerns, please feel free to let me know.
Wish you have a nice day!
Best regards,
Michael
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