Windows Defender zaps apps without asking or reporting

Windows 19041.388 Pro.
App is from 2013, paid for, Koyote Free Video Converter.
If I try to run it I get a very brief busy, and then nothing. Not deleted, just doesn't run. Nothing can be found in Task Manager.

If I disable Windows Defender and reinstall it, it works fine. The moment Defender re-enables itself the app becomes "dead" again.

Defender also has the nasty habit of saying known, safe apps are low risks, kills them, and gives me no option to say allow on this device. Need to disable Defender in order to use them.

Been doing it for about a month.

Hi,
Before you install the app
Download the installer
Right click it and go to properties
Use the Unblock button if it exists/ apply.
Then right click run as admin when installing.

No Unblock on Installer or App. But ran both as Administrator. That worked, thanks.

Also found that by going through Protection History you can view the PUAs and take your choice of action. That solves the problem for all of them.

Not a bad idea.

Hi,
I don't use downloads folder much anymore either I use video/.. anything but downloads for installers....

macnab said:

If I try to run it I get a very brief busy, and then nothing. Not deleted, just doesn't run. ... Need to disable Defender in order to use them.

In my experience when that happens it isn't Defender blocking the app as a false positive, it's Controlled Folder Access blocking the app from reading/writing to a protected folder. Without access some apps cannot run and close, others will run but cannot save files or their settings. Adding the app to the 'allowed' list fixes all that.

Add or Remove Allowed Apps for Controlled Folder Access in Windows 10

That would explain why running as admin solves the problem. Defender doesn't stop it because it is a PUA, low threat.
Will have a look at that handy link. Plus, I now know how to allow/block Low level treats.

- - - Updated - - -

Thanks everyone.
Turns out it was not Controlled Folder Access, because that was off. It is on now.
Running as Administrator seems to be doing the trick.
And maybe it is time to look at a 64-bit aoo,. But this one is just so easy to use. Love the GUI.