No Quinn. Restart has not helped, I am still having the same issue.

Thanks for the response Quinn.While experimenting with packet filters, I came upon a strange error where the application suddenly stopped initializing with the error "SimpleFirewall: [1203:36222]:failed to register with the provider: Couldn't communicate with a helper application".I removed all my changes, deleted the related files and folders and downloaded the sample code again , but still the error persists. So much so, that even a fresh copy of the sample code is throwing the same error. On looking around for this issue, it appears it is kind of a known issue(47227781) and was fixed in xcode11, but I am using the latest version of xcode 11.3.1 and I am still seeing this issue.Is there a workaround for this issue? Has this been not solved yet?

Thanks once again Quinn. I have one more query wrt the packetFilter mechanism:In the NEFilterDataProvider class description, it says "The sandbox prevents the Filter Data Provider extension from moving network content outside of its address space by blocking all network access, IPC, and disk write operations."Are any similar restricitons also applicable to the packet handler function? My implementation is dependent on whether I can transfer the packet out to another module for detailed processing.My idea was to do the following:1. In packetHandler, parse the packet for ethernet ,ip and tcp headers to find if packet needs to be redirected. Default action will be allow.2. If the packet is to be redirected , delay the packet and use ipc or another socket to transfer the NEPacket object for further processing to another module.3. Once the final verdict for the packet comes, allow or drop the packet from the handler.Is this possible?Or are there restrictions on this too, similar to NEFilterDataProvider?

Thanks for the response Quinn.I have watched that video you are referring to. Few followup comments/questions:1. By packet filter are you are referring to NEFilterPacketProvider class?Very little documentation exists for this class. Do we have any sample code for this class? How does one use NEFilterPacketContext ? 2. With respect to the Transparent proxy approach, I dont believe it is suitable for us because we would need packet level filtering.For e.g: We may need to filter traffic based on TCP flags down the line, which I dont think is possible with the NEAppProxyProvider class since it only deals with flows. Is my understanding correct?