3.3.5.19 Processing an RDPGFX_CAPS_CONFIRM_PDU message
The structure and fields of the RDPGFX_CAPS_CONFIRM_PDU message are specified in section 2.2.2.19. The header field MUST be processed as specified in section 3.1.5.1. The graphics capabilities specified by the server SHOULD be stored in the Confirmed Graphics Capabilities (section 3.3.1.14) ADM element and MUST be adhered to by the client.
If the capability set received in the RDPGFX_CAPS_CONFIRM_PDU message is RDPGFX_CAPSET_VERSION103, RDPGFX_CAPSET_VERSION104, RDPGFX_CAPSET_VERSION105, or RDPGFX_CAPSET_VERSION106 then the client can resend the RDPGFX_CAPS_ADVERTISE_PDU message during the connection to reset the protocol. The client MUST reset the channel state after sending the RDPGFX_CAPS_ADVERTISE_PDU message and MUST ignore any messages sent by the server until RDPGFX_CAPS_CONFIRM_PDU message is received.