Hello,
Thank you for posting in Q&A forum.
The issue you're describing where the domain is no longer visible in the "Users and Groups" section and seems to have been removed can be caused by several factors. Here are some potential root causes to troubleshoot the issue:
Domain Trust Issues: The trust relationship between the domain and the virtual machine might have been broken. This can happen due to network issues, changes in domain controller availability, or misconfigurations.
Domain Registration Issues: If the domain registration was not completed correctly or there were issues during the process, the domain might not be properly attached.
Network Connectivity: The virtual machine might be having trouble connecting to the domain controller due to network issues or incorrect DNS settings.
System Changes: Recent updates or changes to the system, such as group policy updates or software installations, might have affected the domain attachment.
Time Synchronization: If the time on the virtual machine is not synchronized with the domain controller, this can cause issues with domain authentication
I hope the information above is helpful.
Best Regards,
Yanhong Liu
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