fast-scanning system antivirus or too fast?

Hello I use CIS 3.8 Beta and scanned system antivirus scan option Computer and scanned in 15 minutes over 85 000 files or do we do it? Or something ignored during the scan, ai or scans registry keys?

CIS ignores file bigger than 20 MB by default. You can change that number in the setting of the Anti virus part. What happens when you set it much bigger?

in settings is Do not scan larger tha 50mb,increase??

Try setting it to 999 MB (that is the biggest size I think you can set). Now scan again and see how long it takes.