Since the release of MacOS X Sierra, Apple has added new security features to its desktop OS. While overall this is a very good thing, it can add an extra step or two when installing some applications, and one of those applications is Blackmagic Design's Desktop Video application.
App Store and Identified Developers Only
If you're trying to install software from Apple's App Store or "Identified Developers," the standard install process works just fine in MacOS X Sierra and newer versions of the OS. However, if you've downloaded an application from the Internet, chances are its creator is not considered an "Identified Developer" by Apple. This helps considerably in keeping your computer more secure from malware and other rogue software applications one may accidentally (or unknowingly) download online. But if you're trying to download reputable software updates, the default settings in MacOS X won't let you install them.
So what to do?
Well, Apple has provided a convenient way to override these security settings. To do so, simply go into your Systems Preferences and into the Security & Privacy pane. Click on the 'General' tab, and look for the area where it says "Allow apps downloaded from:". Underneath, you will see a couple of radio buttons for "App Store" and "App Store and Identified Developers". While the second radio button gives you more leeway in installing applications, it won't be enough for installing Desktop Video.
If you have already tried to install Desktop Video and it has failed due to security reasons, when you go into Security & Privacy, you'll see some additional information below the two radio buttons indicating that Desktop Video was blocked from being installed. Additionally, there will be a button labeled "Open Anyway" next to the message. You'll need to unlock you're Security & Privacy preferences, but once you do, you'll be able to click on the "Open Anyway" button and Desktop Video will operate normally under newer versions of MacOS X.
1) What is the current version of Desktop Video? - The current version of Desktop Video, as of this writing, is 11.4.1, which was released in early October 2019.
2) I don't see what you're describing, but there is a third radio button that says "Anywhere". What should I do?
- The "Anywhere" radio button appears as an option in MacOS X versions prior to Sierra. You can select this option to install Desktop Video if you are having issues. However, please note that if you leave this option enabled, ANY software application can be installed on your computer. Therefore, it is only recommended that you select this option if necessary to install Blackmagic Design's Desktop Video application, and then reset it to one of the more restrictive application installation security options immediately afterwards. We do not recommend that you leave your application installation settings set to "Anywhere" as this may compromise the security of your computer.