Unable to install third party applications on my MacBook air

The app you're referring to is compressed with the 7Zip format. There are several free apps available to unarchive this...although I've never had to use any of them in over 15 years. One I saw in the Mac App Store: https://apps.apple.com/us/app/unzip-rar-zip-7z-unarchiver/id1537056818?mt=12

There are others, too. I'd be leery of a different one I saw on the App Store from MacPaw, as this is the software vendor that hawks CleanMyMac, which several of us now refer to as BrickMyMac.

MacMikeInOK wrote:

The app you're referring to is compressed with the 7Zip format. There are several free apps available to unarchive this...although I've never had to use any of them in over 15 years. One I saw in the Mac App Store: https://apps.apple.com/us/app/unzip-rar-zip-7z-unarchiver/id1537056818?mt=12

There are others, too. I'd be leery of a different one I saw on the App Store from MacPaw, as this is the software vendor that hawks CleanMyMac, which several of us now refer to as BrickMyMac.

Good point regarding MacPaw and CMM aka BrickMyMac

😎

You can install apps from anywhere you want. However, it sounds like you’ve chosen to get those apps from one of the nefarious software aggregators that bundles malware with the installers. You should go to the developer’s website to get legitimate software.

Changing permissions in Get Info was completely unnecessary.

Of course you can install apps from outside the App Store. However, you do so at your own risk. Now if you can tell us exactly where this "malware blocker" resides, and when it appears we may be able to help you, as there is n such app on your Mac by default.

You're not referring to Gatekeeper are you?

jfisher387 wrote:

Seems pretty crazy that I just cannot install from outside the App Store. Your telling me there’s absolutely no way? I’m computer savvy, took a year or so in computer science. I just have no clue on macs.

In MacOS Sonoma, you'll find there are two options for allowing the downloading of software (System Settings-->Privacy & Security):

• App Store
• App Store and Identified Developers

So, no...you aren't "forced" to obtain software from only the App Store.

jfisher387 wrote:

Probably is gate keeper. I’ve heard that one now. What I’m calling the malware protection comes up if you right click an app and hit get info. There is a toggle for malware protection

Never seen it. For software that isn’t notarized, you just ctrl-click on it and choose Open. That clears the quarantine. Perhaps they added a switch to clear it.

There are those who have a genuine Apple Technical Question and seek meaningful tried and test Technical Advise.

Then there are some ( not all ) who seek " their moment in the sun ".

As other have mentioned, purposefully downloading Third Party Applications from UnTrusted Sites or UnTrusted Developers is a sure fired way to inflict all kinds of issues on the otherwise will protected Operating System from Apple

One of those features, the Operating System resides in a Sealed and Read Only Volume that cannot be opened by the User nor by Third Party Applications.

Mac app security enhancements

macOS - Security

Being a bit cheeky here

Apple can’t fix the Users’ choice of Third Party Applications installed and used on this computer.

That falls clearly Out-Side the Domain of Apple and belongs solely with the domain Third Party Application Developers 

Any specific application you have in mind and tried that requires jumping through the Hops ?

If you mention the specific application and or a Link to the Application

I am sure any one appearing in your question maybe willing to try to install it, including myself

jfisher387 wrote:

allowing me to bypass the malware blocker.

Which malware blocker is that?

No answer to your question. (And no answer to why you'd want to install apps from unidentified developers, either).

For further reading regarding what needs be done by the Developers

Notarizing macOS software before distribution | Apple Developer Documentation