iobit not really portable

i think iobit is writing to my disk. i have iobit defrag in portableapps (on my hard drive, not a usb).

i scanned my system for virus' the other day with dr. web cureit. and dr. web reported a pup. iobit is usually detected as a pup, so that was not unusual. but its location was:

c:\windows\system32\iobitsmartdefragextension.dll

it is possible i had iobit many years ago installed and this is a leftover from the uninstaller. so i thought i'd post it here so someone else could check if they have it as well.