Error 0x800720A6

Value: -2147016538 | 0x800720A6 | 2147950758

What does it mean ?

ERROR_DS_CANT_ADD_SYSTEM_ONLY  
It is not permitted to add an attribute which is owned by the system.
Value: 8358 | 0x20A6 | 0b0010000010100110

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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