Hello Pred-martin, (1) Could you please check, if there is any session available on the PAN firewall, Use CLI by using '>show session all filter source IP_ADD_OF_THE_TESTING_PC destination IP_ADD_OF_THE_DESTINATION'. ( Collect the session ID) (2) If there is a session exist for the same traffic, then please apply CLI command PAN> show session id XYZ >>>>>>>> to get detailed information about that session, i.e Application, port, NAT rule, security rule, ingress/egress interface etc. (3) verify the global counters, if a specific "DRP" counter is increasing rapidly. - Create a packet filter under GUI > Monitor > Packet capture -Apply below mentioned command multiple times, while try to establish the RDP connection. ( with 2 seconds interval) > show counter global filter packet-filter yes delta yes The command show counter global provides information about the processes/actions taken on the packets going through the device; if they are dropped, nat-ed, decrypted etc. These counters are for all the traffic going through the device and are useful in troubleshooting issues; like packet loss. It is advised to use the command show counter global filter packet-filter yes delta yes in conjunction with filters to obtain meaningful data. For more information, you can follow the DOC What is the Significance of Global Counters? (4) Could you please share the custom service details ( snapshot) for OPC-UA-4850, OPC-UA-4851, RDP-3390. Hope this helps. Thanks
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