Clarification: I used Control Panel to get to "Associate a file type or protocol with a program." That is where I set my preferred solftware as the default for opening PDF files. This is supposed to be a global setting (as you say), but when I click on a pdf file in a file explorer it is opened by the SureClick browser instead. Somehow, SureClick is overriding the global setting. All other default file associations are indeed global; only PDF is subject to this odd override.
I don't need to uninstall Edge (Microsoft) or SureClick (which seems to be a Chromium-based browser). I only want to stop the override. I do not want to make registry changes to SureClick unless the change is specific to handling of PDF files. From the example given here, such a file-type setting seems unlikely.
It seems as if a macro editor is going to be a better solution. I'm looking for a script to automate "IF filetype = PDF, open with , ELSE open." If I assign that to a hotkey, I can run it instead of clicking on a PDF file. The ELSE statement would account for accidentally running the macro on a non-PDF file.
THANKS, anyway.