Most of the scanners supported by SilverFast 9 are either directly communicated with by it, or SilverFast 9 does install the necessary drivers.
Or there are current drivers you can install without problems.
However, there are some older scanners with drivers from older versions of macOS only.
Although these still work on current macOS, you cannot install them, because you get "Apple can't check for malicious software".
You have used those drivers earlier, and you know they are fine, you just need to install them, and not to get the macOS in the way.
So you override this message. Apple says this is how you do it:
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1. On your Mac, choose Apple menu > System Settings, then click Privacy & Security in the sidebar. (You may need to scroll down.)
2. Go to Security, then click Open.
3. Click Open Anyway.
This button is available for about an hour after you try to open the app.
4. Enter your login password, then click OK.
The app is saved as an exception to your security settings and you can open it in the future by double-clicking it, just as you can any authorised app.
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