After using the update feature within RC6 and clicking through the options received the error msg.
Background: Had updated from RC5 to RC6 with no problems. Read through updates and saw where there was the other update for HiDPi usage. Manually downloaded and installed it but saw no difference due to later finding I did not have a HiDPi monitor. Had also received the error msg about not finding the designated directory when trying to open reg Scrivener RC6 after installing RC6 HiDPi. Uninstalled RC6 HiDPi from computer and reinstalled RC6.
Have full admin rights and tried a second time with same error.