In Windows Vista and Windows 7 when you run some privileged commands from command prompt you may get system error 5. On these Windows editions, commands that need administrator privileges should be run from elevated command prompt. Otherwise we would get this error like below.
C:\>net user techblogger /add System error 5 has occurred. Access is denied.
Now open elevated administrator command prompt as explained in the below article.
Now if you run the same command from the elevated command prompt you will not see any issue.
C:\Windows\system32>net user techblogger /add The command completed successfully. C:\Windows\system32>