One System Care is a Registry cleaner and system optimization program that states it can increase a computer’s performance and privacy by cleaning the registry and removing unnecessary files. Many of the detected issues are not actually an issue for the computer. Many anti-virus and security products detect this program as a Trojan, PUP, or adware program, I feel that feel this program should be avoided. As Microsoft does not feel users should use these types of tools in the first place, I recommend that you remove this program from your computer.
Source: https://www.bleepingcomputer.com/virus-removal/remove-one-system-care-registry-cleaner