Pulled security update caused flood of issues
https://www.bleepingcomputer.com/news/microsoft/microsoft-addresses-issue-breaking-windows-10-reset-this-pc/
Microsoft has resolved a known issue that caused the Windows 10 "Reset this PC" feature to fail in some cases, on both client and server platforms.
The 'Reset this PC' feature allows Windows 10 customers to reinstall the operating system using either a local recovery image or the latest Windows 10 version available on Microsoft's servers.