Error 0x801901A1

Value: -2145844831 | 0x801901A1 | 2149122465

What does it mean ?

HTTP_E_STATUS_EXPECTATION_FAILED  
Expectation failed (417).
Value: 417 | 0x01A1 | 0b0000000110100001

Where does it come from ?

FACILITY_HTTP  
HTTP support
Value: 25 | 0x019 | 0b00011001

Other Errors for FACILITY_HTTP