Norton Utilities Ultimate purchased and exe file downloaded but it will not install

Thanks for that. I've tried to do as you suggested, but have run into a problem when uninstalling Norton Utilities Premium - I only have NUP, not just NU. The uninstall process starts off OK but then hits a 'delete file error' and fast scrolls through the same files over and over. But the green band which shows progress on the uninstall process comes to a halt! So the uninstall seems to have failed!

1. Have not used windows admin user account for anything 2. I've now restarted as you've described and attempted both installing Utilities Ultimate and uninstalling existing Utilities Premium app. I got the same result as before ie installation fails to complete and uninstall fails also. 3. I've found a Norton item 'Fix problem upgrading Utilities Premium to Utilities Ultimate'. In it, the first step is 'open Norton Utilities Premium' But I can't find Norton Utilities Premium other than in the apps list for uninstalling! Could that be a clue to my problem - it seems to me that the Utilities Premium app is corrupt (and won't uninstall), and maybe that is the reason why Utilities Ultimate won't install. Does that make any sense? Otherwise I'm still stuck! When I look at uninstalling stubborn apps, one of the options suggested is to use a (Norton) uninstaller. Does that exist anywhere?

First: OS is Windows 10 & version is 21H2. I believe it's fully up to date.

Next: I've deleted the 2 NUP files I found in Program Files, restarted and tried installing the NUU download exe file again. No success I'm afraid. Same as before: the window 'Installing Norton Utilities' comes up, with 'The wizard is upgrading your product'. But it doesn't advance any further..... It shows in Task Manager - not completely inactive - cpu usage occasionally reaches as high as 4.5%, but also drops to 0. But essentially nothing happens.

Your observation about where it says 'download failed' is just what I get. But in contrast with your situation, there are no NU files to be found on searching, apart from the download exe files which won't install. Certainly no app files. 

I still suspect that the source of the  problem is the pre existing NUP item which cannot be uninstalled. I can get the uninstall process to start, and it runs until it reaches a point where it says 'Delete File error : C/ProgramFiles/CommonFiles/microsoft Access to the path is denied at System IO FileSystem Info set......'  then the code whizzes by fast and keeps returning to the same thing again and again. I think I need to find a way of being able to uninstall this before I can get NUU to install.

Thanks for all your help and advice Peterweb. I think you've helped me get a bit closer to a solution. I'll post the outcome from what arises from Norton Support.

One further thing that I've done which I think further clinches the uninstallable NUP item as being the culprit. I used CLI to generate a list of apps on my PC (Get - AppxPackage l ft name, PackageFullName - autosize) using PowerShell. There were no Norton Utiities items listed - the only Norton item was Norton Securities. I therefore conclude that a full app for Norton Utilities does not exist, and that the NUP item which comes up when I use the Uninstall Apps facility  can only be a remnant of a previous unsuccessful download that is still in the registry. It dates from 2020, and I can recall being offered a free 'upgrade' by Norton. I watched it being downloaded at the time, and it failed to complete spectacularly by going into a spin of flashes of code - rather like what happens when I try to uninstall now!  I didn't pursue it with Norton at the time (it was only a freebe after all), and I certainly never got Norton Utilities Premium. What I didn't realise at that time was that although the download had failed, it had succeded to leave a telltale somewhere!  I think it's too much of a coincidence that I now (2 years later) have another download failure for a Norton Utilities item on the same computer - there must be a link, and I strongly suspect that if this remnant/vestige/string is removed then the NUU will upload like magic!