It might help if I spell out the problem. The old computer was giving me the error message Diagnostics Policy Service is not running." It happened once, I used my laptop to search on that term, and found how to set things to have it working again. A few months later, it happened again, and I found I had to do something a little different, but again in worked. The last time it offered up this Windows error message there was no way to reset it. I could have simply reinstalled the computer, but then I would lose all of the software, much of it can only be installed once (though I could beg the company, telling them it is the same computer, to get a new service key), but others I installed when I was part of a group that had company access to the software. As a retiree I can continue to use it but I can't get a new copy of it. That computer is robust, a quad core HP, but it's nine years old. So I bought a new one, installed some software from work that I can still use and other things I had older versions I already paid for. The Adobe software is the real gem in the old machine, it's the last version that was on disk that I own outright, from before they went completely to the Cloud and monthly rental of the software.

So I'm trying to streamline the work between the two, not keep loading it onto thumb drives to go back and forth. The old one, in this state, will never communicate with any network unless there is a physical connection. I can't take the hard drive out of the old machine because the software understands that it is in that computer and won't work in the new one. There are theoretical ways to trick the software into thinking it's in the same computer, but that's a lot of jumping through hoops and isn't guaranteed except to possibly mess up everything. $1600 for the new computer means I have an up-to-date system and it doesn't have the same glitches the old one did (the Windows fire wall and real-time protection on Malwarebytes could never be set to run. I had to use Zone Alarm or something like that as my firewall.)

The cable has one end that is the "drive" and the other end is the standard USB. If I'm willing to plug and unplug this cable between the two computers, I'll do it where it's easiest to reach, on the new computer (leaving the other end in the old computer). So which end should I use for plugging and unplugging, the fat drive end or the USB end - or does it matter since it's all basically one drive device?

My plan is to have a distinct upper-level folder (desktop, probably, or even a new Library) landing pad in each computer that I can easily navigate to where I can put the files I want to move back and forth, so I'm not crawling through one or the other beyond that folder.

Fussing about computers every so often is an exercise that means I do research and try new things. I suppose it's good for me. :-)