Error 0x803D0019

Value: -2143485927 | 0x803D0019 | 2151481369

What does it mean ?

WS_E_PROXY_REQUIRES_DIGEST_AUTH  
The HTTP proxy server requires HTTP authentication scheme 'digest'.
Value: 25 | 0x0019 | 0b0000000000011001

Where does it come from ?

FACILITY_WEBSERVICES  
Web Services
Value: 61 | 0x03D | 0b00111101

Other Errors for FACILITY_WEBSERVICES