I agree. It seems to me that there are potentially different root causes of the PFE12000 error, based on the different ways people have achieved success, whether temporary or permanent. In my case, I had the PFE12000 error from when I first installed the app, and worked around it by connecting over 4G - specifically without changing anything locally on the device with the error (no de-install, re-install, no change to time, no change of firewall Windows firewall settings, etc. etc.). And I had the same problem on two devices, and both are now working as a result of connecting over 4G first. That suggests the root cause in my case was not local to my devices, but with connectivity, to some unspecified pre-req.
So I had the error and the 'solution' was not the one marked as such in this thread. And I know a number of people have resolved it using the same approach. But that approach is a workaround, not a solution; as has been said many times - the application should just work in a consumer environment where a lot of the customer base is not technical. At the very least, if there are pre-requisites for success, such as ensuring Windows firewall isn't blocking certain ports, or requiring a certain OS patch level, or a router requiring a supporting configuration, or anything else, etc. etc., they should be published so that people can ensure they meet the criteria before installing the app. They're not, so one assumes it should just be a case of installing the app, and away you go....
When the issue has a proper solution, it would be nice to know from Sky what the root cause(s) is / are, and not just be fobbed off with a 'install the latest, greatest version - nothing to see here' type statement. I highly doubt Sky will be that candid though.