I have filed a bug report with Adobe regarding this problem. I am running Adobe CC on a Windows 10 Pro system.
There are 2 basic issues that have arisen.
1. The link between LR and PS isn't working.
2. Every time I open PS I get the dialog box, "Do you want this app to make changes to your device", as if I was trying to install the program. I click yes and the program opens.
Regarding 1. When I click on Edit in PS CC 2017, I get the dialog box mentioned in 2. I click through PS opens but the file from LR does not open in PS. About 30 sec later I get a dialog box in LR saying "The file could not be edited because Adobe PS 2017 could not be launched". even though I had just launched PS by clicking through its dialog box. When I click through the LR dialog box the file opens in PS. But when I try to Save the file in PS after editing it is not saved in LR. In order to get it into LR I have to import it. So the link between LR and PS is broken in both directions. Rather than go through that charade I'll often just use File/Open in PS to get it into PS and then import the edited file in LR since I have to do that anyway. This is a workflow killer and is very annoying. I tried Uninstall/Reinstall PS but nothing changed. I'm being charged $9.99/mo. for CC and the connection between its two components is nonfunctional.
Regarding 2. This happens every time I open PS whether directly or through LR.
As I noted above I registered a bug report with Adobe about 3 weeks ago regarding this matter.
An update and clarification to my post.
From my post above: "About 30 sec later I get a dialog box in LR saying "The file could not be edited because Adobe PS 2017 could not be launched"."
I was guessing the 30 sec time lag in LR. I just timed it. It was 1:50! Almost 2 minutes just to inform me that the file wasn't transferred to PS. And I am running an Intel i7-6700 CPU@ 3.4 GHz so it's not due to a slow computer. This is a major workflow killer.