'Virus Check' software?

ClamXav, its free and works well with my iMac

 

But, if you're not using those downloads in a Windows partition, or passing them to someone who is, then you don't need any virus checker, because there are no viruses that affect Macs.

Check out this link by GGJstudios,
http://guides.macrumors.com/Mac_Virus/Malware_FAQ

 

You are asking the wrong question. A virus is something that hurts you just by going to a website, or by downloading something. There are no Mac viruses in the wild. You _are_ in danger if you turn off common sense: If you download and try to run something that can hurt you, your Mac will warn you. Repeatedly. If you ignore the warnings, you can get hurt.

An example: You go to a website and it tells you your Mac is infected by viruses. (They are lying. Your Mac isn't infected, and if it was, they couldn't detect it). They ask you to download and install software to remove the virus. (Since they were lying in the first place, it should be obvious that installing their software is a bad idea). You download and run the software. Your Mac asks you at least twice if you want to go ahead. If you do, the consequences may be bad.

 

Unless you're downloading torrents, from unknown sites or naughty stuff, you don't need a virus scanner with OS X. The only thing they do is slow down your system.

 

You already have Xprotect. If you are that paranoid, turn on gatekeeper, remove java and remove flash. Done.

 

Use Magician.

 

If you're downloading pirated software, don't. That's a good way of introducing malware to your Mac. If you're downloading pics, movies, music, etc., you're fine.

Macs are not immune to malware, but no true viruses exist in the wild that can run on Mac OS X, and there never have been any since it was released over 10 years ago. The only malware in the wild that can affect Mac OS X is a handful of trojans, which can be easily avoided by practicing safe computing (see below).

3rd party antivirus apps are not necessary to keep a Mac malware-free, as long as a user practices safe computing, as described in the following link. Read the What security steps should I take? section of the Mac Virus/Malware FAQ for tips on practicing safe computing.

No, don't. Not only do you not need such apps, I wouldn't trust such software being sold by some guy out of his apartment.

You don't need to "maintain" your Mac and you don't need "cleaner" or "maintenance" apps to keep your Mac running well. Some of these apps can do more harm than good. Some can even degrade, rather than improve system performance.

Some remove files/folders or unused languages or architectures, which does nothing more than free up some drive space, with the risk of deleting something important in the process. These apps will not make your Mac run faster or more efficiently, since having stuff stored on a drive does not impact performance, unless you're running out of drive space.

Some of these apps delete caches, which can hurt performance, rather than help it, since more system resources are used and performance suffers while each cache is being rebuilt. Caches exist to improve performance, so deleting them isn't advisable in most cases.

Many of the tasks performed by these apps should only be done selectively to troubleshoot specific problems, not en masse as routine maintenance.

Mac OS X does a good job of taking care of itself, without the need for 3rd party software. Among other things, it has its own maintenance scripts that run silently in the background on a daily, weekly and monthly basis, without user intervention. You can use Maintidget to see the last time these scripts were run.

Five Mac maintenance myths​