Hello @Yaroslav Kraus ,
Thank you for posting here.
Based on the description "I have the problem that I am getting an "System error 5 has occurred. Access is denied." when I am trying to run a command "net user /domain <username>" with a regular domain user account (not domain administrator or local administrator).", did you mean you log on one domain client or member server using one normal domain user account (such as daisy) and then run the command net user /domain daisy, then you got the error message "System error 5 has occurred. Access is denied"?
If so, would you please check if you log on another domain machine using daisy account and run the command net user /domain daisy, will you get the same error message?
If so, would you please check if you log on this problematic domain machine using another domain user account (such as daisy1), and run the command net user /domain daisy1, will you get the same error message?
From the above test, we can check the issue is related to one domain machine or one specific domain user account.
Hope the information above is helpful to you.
Should you have any question or concern, please feel free to let us know.
Best Regards,
Daisy Zhou
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