I have scanned (Version 17.4 (9cf9975e9ca8)) my mid 2012 MacBook Pro (OS X Yosemite 10.10.5) three times and each time the scan revealed 12 threats and the scan crashed before completion. Please Help!
Maureen,
I can understand how upset you must be.
Please provide me screenshots of the detection message of 12 threats by following this article: https://support.apple.com/en-us/HT201361.
As full path of detection is not fully visible from UI very often, please provide us with the full path. You can copy the path by right clicking on the detection path and pasting it to the email that I've sent you to send me the Logs. Please check your mailbox. Check your Junk/Spam folders also.