Possible duplicate of How do I install Skype?

@karel I think the problem here is rather that OP deactivated the update source in any way and now Skype doesn't update automatically any more. That's a different thing IMO.

@dessert Your answer to this question is a duplicate of David Foerster's answer to my linked duplicated question for which I awarded David Foerster a +100 point bounty. David Foerster deserves that reputation credit in my opinion for posting the same answer (and answering a famous question) before you did. And since it's a famous question, that's also where David Foerster's answer will do the most good for Ubuntu users generally.

@karel On the contrary, David Foerster's answer does not at all adress the issue that the repo got removed or deactivated, therefore the command to add it (again) doesn't appear there. It's related of course, but reinstalling is neither the only nor the best solution here.

@dessert David Foerster addressed that same issue in an edit that he made to the top upvoted answer to the duplicate question that I linked to. To make sure that people would read it the relevant text was highlighted as bold font text in the first paragraph of the edited answer.

@karel Yes, I'm totally aware that reading the first answer is not enough. Still, his answer(s) doesn't address this exact issue. Do you find anything like sudo add-apt-repository deb https://repo.skype.com/deb stable main in any of the answers there?

@dessert Because of your unique answer I'll flag this question to be migrated if it is closed. The whole purpose of the bounty was to help users to find whatever help they needed to install Skype quickly and easily at one unique famous question. You can see the problem. Ask Ubuntu is choking on multiple 100 point and 200 point "how do I install Skype?" questions, and only one of them works, so Ask Ubuntu users are finding it impossible to quickly get help installing Skype when they need it despite all of our efforts to the contrary.

@karel Yes, I know and understand this issue and what you're trying to do is good, but this question is not at all about installing Skype, but rather about getting it to work again after it seized to work due to failed/missing updates.

dessert, your answer is based on the assumption that OP has somehow installed the skypeforlinux package and later disabled Microsoft's repository that would normally lead to automatic updates of said package.

If that is the case then I agree with you that askubuntu.com/a/932189/175814 wouldn't solve the problem in the long run but only until the next available package update. Therefore the linked question couldn't be a duplicate of this one.

However, I think that there are multiple other possible reasons why the package wasn't updated automatically, e. g. because OP disabled automatic updates altogether or there's an underlying repository or package management issue that prevent all (automatic or manual) updates.

I suggest that we ask OP for more information. I'll make the start.

Adding the repository and updating worked for the OP according to his comment.

Hm… I don't see that comment but I'll take your word for it.

That would (mostly) confirm desserts theory in which case I think this question should be rephrased/retitled and kept open.

@karel: What about the new title?

It's definitely an improvement.

The new title would clarify that the question is (a) about the new Skype for Linux and (b) no simple "How do I install X?" question.

Ah, now OP's comment on the answer shows up for me.

Just to clarify: I took “Skype for Linux” as a sign OP meant the “new” Skype because the “old” Skype was just called “Skype”, and as installing the new one automatically adds the repo there must be something wrong with that – whatever exactly it is.

Thanks for clearing that up and changing the title, I think it's clear now.

Now that we made that clear, let's both delete the comment mess.

@DavidFoerster This article is also relevant to the question so I am sharing a link to it: Complaining works! Skype Preview update fixes one major issue. It's too bad I didn't find it and read it before.