Hello 寺田順一, Thank you for posting in Q&A forum.
Here are the answers for your references: (1)Normally, when the name of a computer is changed, the old name will not be displayed in the computer list and the system will update it to the new name. (2)When you change the computer name and log in as a domain user, the new computer name should be automatically updated to Active Directory. However, this update process may take some time and wait for automatic synchronization to occur (such as AD replication). (3)According to my operation, under normal circumstances, the old computer name will not be retained. In addition to using "ping" to check communication at the command prompt, there are also the following methods to distinguish active computers: Active Directory Users and Computers: Open this administrative tool and view the properties of the computer objects. In the "Properties," you can see information such as the last logon time and the computer's DNS name, which can help you identify which are the active computers. PowerShell Command: You can use PowerShell commands, such as Get-ADComputer, to retrieve detailed information about all computers in the domain. You can also filter for specific information as needed, such as the last logon date, etc.
Here is a test in my lab.
Before changing domain PC name.
After changing domain PC name.
I hope the information above is helpful. If you have any questions or concerns, please feel free to let us know. Best Regards, Daisy Zhou
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