A user brought me a laptop. Programs and Features shows 116 things installed, some I recognize and some I don't, many of them are obscure media handlers which probably came with bloatware; any of which might be causing a conflict of some sort. It is running Windows 10 Pro, 1703 x86 15063.504. It seems that the entire appx subsystem has gone nuts. Specific symptoms include: - Start menu: right click anything, or click the power or user bubbles, the popup appears and instantly disappears. - Cortana: the "Type here to search" field flickers and you have to click in it multiple times and pound the keyboard to get it to search anything. - Notifications: click it, the notifications bar slides out then instantly slides back. - Network, sound, battery, clock, basically any of the UWPs on the right side of the taskbar, click them, the expected thing pops up but disappears instantly. - Store and other UWP apps: any text entry field flickers or is untypeable; window borders, size controls and taskbar icon flicker; items with popup menus appear then disappear instantly. This has persisted through sfc, dism restorehealth, upgrade reinstall from iso image, the SoftwareRepairTool and startmenu troubleshooter. However, I swapped the SSD with another and did a clean install, everything works perfectly so it is not a hardware issue, it is something in this particular image. Short of doing a "Reset this PC" keeping the user's files but forcing them to reinstall everything else, what else can be tried to troubleshoot this issue?