Error 0x800721C4

Value: -2147016252 | 0x800721C4 | 2147951044

What does it mean ?

ERROR_DOMAIN_SID_SAME_AS_LOCAL_WORKSTATION  
The domain join cannot be completed because the SID of the domain you attempted to join was identical to the SID of this machine. This is a symptom of an improperly cloned operating system install. You should run sysprep on this machine in order to generate a new machine SID. Please see http://go.microsoft.com/fwlink/?LinkId=168895 for more information.
Value: 8644 | 0x21C4 | 0b0010000111000100

Where does it come from ?

FACILITY_WIN32  
Provides a way to handle error codes from functions in the Win32 API as an HRESULT. (Error codes in 16 - bit OLE that duplicated Win32 error codes have also been changed to FACILITY_WIN32)
Value: 7 | 0x007 | 0b00000111

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