The certificate presented could not be parsed or failed validation.
The certificate failed to load because a password was incorrect. Since: 2.72
The TLS handshake failed because the server requested a client-side certificate, but none was provided. See g_tls_connection_set_certificate().
The TLS connection was closed without proper notice, which may indicate an attack. See g_tls_connection_set_require_close_notify().
The TLS handshake failed because the peer's certificate was not acceptable.
The TLS handshake failed because the client sent the fallback SCSV, indicating a protocol downgrade attack. Since: 2.60
Miscellaneous TLS error
The TLS handshake failed because the peer does not seem to be a TLS server.
No TLS provider is available
An error code used with %G_TLS_ERROR in a #GError returned from a TLS-related routine.