If I google either of
Skype.app can't be opened because it is from an unidentifed developer.
Your security preferences allow installation of only apps from the Mac App Store and identified developers.
I find prior discussions. Have you looked at those?
Bob
I had trouble signing in to Skype a few weeks ago. Finally, created a new user name and psw. I was able to connect until a couple of days ago. Got this message on my screen:
Skype.app can't be opened because it is from an unidentifed developer.
Your security preferences allow installation of only apps from the Mac App Store and identified developers.
Don't know what the next step should be.
I

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