

Your computer may still play a sound for new messages even though you’ve turned notifications off in Skype. Why does my computer make a sound when I send a Skype message? Note: Notification settings are not stored on your device when you sign out of Skype and select No when asked if you want to remember the account and application settings on the device. To stop your computer from playing a sound when you get a new Skype message, select Settings > Notifications, and then switch Notification sounds off or on. How do I stop notifications in Skype on desktop? To stop your device from playing a sound when you get a new Skype message, select Settings > Notifications, and then toggle Notification sounds off or on. How do I turn off Skype notification sounds?
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Under Notification settings, toggle “Show out of app ongoing call indicator” off.

How to stop this skype window from popping up. How do I stop Skype from popping up on Windows 10?
