Windows 10 build 18950 is out but it doesn’t come without its faults.
Build 18950 deletes MS Store apps, to the users’ despair
Upgraded twice from 18362.239 offline, upgraded from 18362.267 offline and then tried online with same results. The store App and all related apps, Calculator, Mail, Feedback Hub and many more are gone. This was on a total clean install of 18362.
And here’s the OPs screenshot:
Upgrading online or offline brings the same result. Also, using PowerShell, a Local account, or an Administrator account, doesn’t solve the problem.
For now, Microsoft has not addressed the problem and there aren’t any official resolutions.
Stay close, as we will update you as soon as a working solution is found.