For those still having to use Windows 7 after end of support, I would recommend the same advice when support ended for XP...Forced to use Windows XP...Ditch the Free AV - Get a Paid Solution

Although not specifically an anti-virus (see here) Malwarebytes for Windows Premium still supports older operating systems like Windows XP SP23, Vista SP1, and Windows 7/8/8.1. However, it has limitations as explained by David H. Lipman (a trusted Security Colleague and Malware Researcher/Analyst) and the anti-ransomware protection component is only available on Windows 7 or higher. The free version is strictly a stand-alone scanner that detects and removes malware when you run a scan...it does not provide real-time protection to prevent infection.

I no longer recommend avast or AVG as a free alternative anti-virus solution...I explain why in this topic.