我在 AWS 上有一台 RedHat Enterprise 7 机器，安装了 Xvnc 和 Xrdp。Xvnc 设置了密码保护，但没有用户名。
如果我使用 VNC 查看器 (TurboVNC)，我可以使用密码连接到 VNC 会话（通过 SSH 隧道）并查看桌面。但是，当我使用相同的 Microsoft RDP 客户端时，我可以看到 Xvnc 会话：
但它不接受任何凭证。登录总是以“显示 0 登录失败”结束：
这是的输出xrdp.log：
[20210514-10:15:04] [INFO ] starting xrdp with pid 5123
[20210514-10:15:04] [INFO ] address [0.0.0.0] port [3389] mode 1
[20210514-10:15:04] [INFO ] listening to port 3389 on 0.0.0.0
[20210514-10:15:04] [INFO ] xrdp_listen_pp done
[20210514-10:16:15] [INFO ] Socket 12: AF_INET connection received from 127.0.0.1 port 52100
[20210514-10:16:15] [INFO ] Using default X.509 certificate: /etc/xrdp/cert.pem
[20210514-10:16:15] [INFO ] Using default X.509 key file: /etc/xrdp/key.pem
[20210514-10:16:15] [WARN ] TLSv1.3 enabled by config, but not supported by system OpenSSL
[20210514-10:16:15] [WARN ] libxrdp_force_read: header read error
[20210514-10:16:15] [ERROR] out xrdp_mcs_disconnect error - 2
[20210514-10:16:17] [INFO ] Socket 12: AF_INET connection received from 127.0.0.1 port 52102
[20210514-10:16:17] [INFO ] Using default X.509 certificate: /etc/xrdp/cert.pem
[20210514-10:16:17] [INFO ] Using default X.509 key file: /etc/xrdp/key.pem
[20210514-10:16:17] [WARN ] TLSv1.3 enabled by config, but not supported by system OpenSSL
[20210514-10:16:18] [INFO ] connected client computer name: PCAZRW01184
[20210514-10:16:18] [INFO ] client supports 40 bit encryption
[20210514-10:16:18] [INFO ] client supports 128 bit encryption
[20210514-10:16:18] [INFO ] client supports 56 bit encryption
[20210514-10:16:18] [INFO ] client supports fips encryption
[20210514-10:16:18] [INFO ] adding channel item name rdpdr chan_id 1004 flags 0x80800000
[20210514-10:16:18] [INFO ] adding channel item name rdpsnd chan_id 1005 flags 0xc0000000
[20210514-10:16:18] [INFO ] adding channel item name cliprdr chan_id 1006 flags 0xc0a00000
[20210514-10:16:18] [INFO ] adding channel item name drdynvc chan_id 1007 flags 0xc0800000
[20210514-10:16:18] [ERROR] error unknown xrdp_sec_process_mcs_data tag 0xc006 size 8
[20210514-10:16:18] [ERROR] error unknown xrdp_sec_process_mcs_data tag 0xc00a size 8
[20210514-10:16:18] [INFO ] xrdp_load_keyboard_layout: keyboard_type [4] keyboard_subtype [0]
[20210514-10:16:18] [INFO ] xrdp_load_keyboard_layout: model [] variant [] layout [gb] options []
[20210514-10:16:18] [INFO ] TLS connection established from 127.0.0.1 port 52102: TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256
[20210514-10:16:18] [INFO ] xrdp_caps_process_pointer: client supports new(color) cursor
[20210514-10:16:18] [INFO ] xrdp_process_offscreen_bmpcache: support level 1 cache size 10485760 MB cache entries 100
[20210514-10:16:18] [INFO ] xrdp_caps_process_codecs: nscodec, codec id 1, properties len 3
[20210514-10:16:18] [WARN ] xrdp_caps_process_codecs: unknown codec id 5
[20210514-10:16:18] [INFO ] xrdp_caps_process_codecs: RemoteFX, codec id 3, properties len 49
[20210514-10:16:18] [INFO ] Loading keymap file /etc/xrdp/km-00000809.ini
[20210514-10:16:18] [WARN ] local keymap file for 0x00000809 found and doesn't match built in keymap, using local keymap file
[20210514-10:16:18] [ERROR] libxrdp_query_channel - Channel 0 name rdpdr
[20210514-10:16:18] [ERROR] libxrdp_query_channel - Channel 1 name rdpsnd
[20210514-10:16:18] [ERROR] libxrdp_query_channel - Channel 2 name cliprdr
[20210514-10:16:18] [ERROR] libxrdp_query_channel - Channel 3 name drdynvc
[20210514-10:16:18] [ERROR] libxrdp_query_channel - Channel out of range 4
[20210514-10:16:18] [INFO ] drdynvc_process_capability_response: DVC version 3 selected
[20210514-10:16:31] [INFO ] xrdp_wm_log_msg: sesman connect ok
[20210514-10:16:34] [INFO ] xrdp_wm_log_msg: login failed for display 0
我保留用户名为空并输入 VNC 密码。有什么问题，我该如何修复？