I just finished running a bootscan and there were detections of [PUP] in 9 locations. Some were the same [PUP]. Win32:Dropper-gen [Drp] is the one associated with SoftwareUpdater.Ui.exe and is in the chest now. Hope that fixed it for good. SoftwareUpdater folder is still in my Program Files (x86) containing config, Maintenance.exe, SoftwareUpdater.Bootstrapper.exe, SoftwareUpdater.dll and SystemStore.exe but the file SoftwareUpdater.Ui.exe is GONE. Yay!
I see now I didn't have the Scan All Files box checked in the Scan Parameters for Full System Scan and Quick Scan, so I hope by checking that now that the [PUP] files will be detected from now on.
Thanks for your replies and help.