When clicking on security settings, the following in included with Administrators, INTERACTIVE and me - Account Unknown(S-1-5-21-1264974048-2684354138-3279359898-1000) I am a concerned that this could be malware or bug. The updated programme took about 30 minutes to download, and my system is now extremely slow,
See item 10 in this link and use one of them to get help for possible infections.
Try to include what operating system you use and details of what you are concerned about when you make a post at one of the listed forums.
https://forum.piriform.com/index.php?showannouncement=15&f=4