After I installed CC Portable and then pasted my license into the space for it and registered successfully, so that I would have CCleaner Professional Portable, which was what I wanted, I checked the registry and found a new Piriform key in Current User and a Piriform key, with a LOT of data in it, in Local Machine. I have danced around this topic before on this forum without coming to any conclusion. I do not have CCleaner Portable on a flash drive; I have it on my PC's hard drive. But I would like it to leave my registry alone, so I make sure the box is ticked that calls for the .ini to be in the folder with the executable, and all settings to be kept there.
It seems that it is impossible to have CCleaner Professional Portable, but I don't think I understand WHY.
I don't care about the Driver Updater. I just want the other Professional features without the registry entries.