I was a Norton Utilities fan back in the DOS days (before Windows). Norton Antivirus was one of the first and best anti-virus utilities out there. Unfortunately, it became bloated and significantly slowed down my computer performance.
While researching for a new solution, I found ESET's NOD32 anti-virus solution. It's one of the highest recommended anti-virus solutions available and it doesn't affect computer performance! I am now a happy user of NOD32 and even purchased a 3 year subscription for 4 computers, what a deal!! My computer hasn't been infected since I installed it and the computer performance improved dramatically since removing Norton (Also McAfee on another computer) and installing NOD32!
Try it, you won't believe the difference!
If you don't like that one, try Malwarebytes
https://www.malwarebytes.com/premium