Thank you Techman and paulbates for your suggestions. I finally got everything working properly. It seems with the first attempt the new 2413u PLM was DOA out of the box. Fortunately I had purchased two of them when Insteon came back from the dead, so I started the process over with the second new PLM which was definitely not DOA but I still had an endless loop of repeating "System Busy" progress bars with no success in restoring the PLM. The Tools-Diagnostic-PLM Status menu was still showing the PLM as "not connected". So I started over a third time. This time I first factory reset both the PLM and the EISY. Without connecting the PLM, I powered up the EISY and ran Upgrade Packages again, just to be sure. Then I shut down the EISY. Then I first powered up the PLM and connected it to the EISY and only then powered up the EISY in hopes that it would finally detect the PLM, before running the IoX Restore routine. At first the "clean" EISY did not detect the PLM--still showed as "not connected" in the diagnostic. But with nothing to lose, I went ahead and ran IoX Restore and when it was completed, the EISY did, finally, see the PLM. Most of my Insteon devices were immediately operable but several were not (e.g. numerous RemoteLincs and a few garden variety SwitchLincs). So finally I had to run Restore Devices and then one-by-one put the RemoteLincs into manual linking mode--somewhat tedious! I did find one IOLinc in my garage now to be dead, but after 10+ years of faithful service I can't complain about that, and fortunately they are once more available at Insteon. Going into all of this, my biggest fear was that my Zwave devices (15 of them) would not migrate and I would have to reset each of them individually, but they all migrated without problems. Whew.