What Happened to Skype?
Everyone uses Skype. That’s why MS bought it. But something is terribly wrong. 
I use Skype on multiple devices, and it’s no longer in-sync. My laptop is marking lots of conversations as unread, even though I read them – even responded to them – on my desktop. This was an old problem that was fixed years ago, but it is back.
That’s half the problem – the other half it does not sync the full conversation anymore. Someone reached out to me 2 weeks ago about a meeting this week, but I didn’t see it until yesterday. That message was only on my smartphone. I responded last night from my smartphone, and that entire thread is missing on my desktop. The resule is 1) No meeting this week, and 2) I told him that next time to use Email. He said he was also having all kinds of Skype issues too.
Microsoft moved away from the P2P architecture of Skype to a centralized model hosted on Azure, and I think they forgot a few things. I hope they get this sorted soon.