The log you're seeing in Event Viewer is basically "informational" in this case.. The Account/User Name in such logs may be "System" , "Network Service", etc. and it occurs when the local system account uses the system admin account (NT Authority) to load/unload a Windows level service or sometimes a 3rd party service. The different domain names are related to the service being run and the type of admin account it needs to use. You generally don't need to worry about these.
Hope this helps.
Grif
Hi all,
First time posting here, trying to find out new things about Windows 7 (my current OS) and perhaps dispel security concerns.
Been looking in Event Viewer and have noticed many instances of the Event 'Special logon'. The subject's domain name is either my PC's name or the name 'NT AUTHORITY'.
What is a special logon, what causes it and why does it have differing domain names?
I can provide more information on request.

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