Error 0x8004257F

Value: -2147211905 | 0x8004257F | 2147755391

What does it mean ?

The operation cannot be completed because the volume is synchronizing.
Value: 9599 | 0x257F | 0b0010010101111111

Where does it come from ?

COM/OLE Interface management. FACILITY_ITF is designated for user-defined error codes returned from interface methods
Value: 4 | 0x004 | 0b00000100

Other Errors for FACILITY_ITF