Malwarebytes anti-malware (Free version)
Malwarebytes Anti-Malware is by far one of my favorite anti-malware programs. I use malwarebytes as a backup to my Anti-Virus program, in case my AV program misses a threat. The free version of Malwarebytes Anti-Malware contains two types of scans, Threat scan and custom scan. The Threat scan, scans all of the possible places malware is known to hide such as in the startup process, registry and other parts of the file system.
The Custom scan gives you the option to choose what files and folders you want to scan.
For example on one of my computers (yes I have several) I have omitted a folder containing viruses (used for testing) and another folder containing investigative tools. Had I not done so, malwarebytes or my Anti-Virus program would have deleted my testing / tool files.
I recommend downloading Malwarebytes Anti-Malware (https://www.malwarebytes.org/antimalware/) and running it at least weekly in order to further protect your computer.
If you have a Mac you can download the Mac version here (https://www.malwarebytes.org/antimalware/mac/)