Guacamole server is unable to make rdp connection with windows system and guacd library will throw this exception because windows remote desktop setting is not enabled.
Enable remote desktop setting:
this will solve the problem, if not make sure firewall ,antivirus and windows defender are turned-off as well in-case.
Enable remote desktop setting:
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this will solve the problem, if not make sure firewall ,antivirus and windows defender are turned-off as well in-case.