It is the most common theming story in the world: everything looked perfect, Windows updated overnight, and by morning the theme is broken, half-applied or gone. This is not bad luck - it is how deep themes and updates collide. Here is why, and the calm order to fix it.
First, understand the collision. A deep visual style needs Windows to load unsigned theme files, so a theme patcher modifies system files - the very files Windows Update exists to replace. When a cumulative or feature update installs fresh copies of those files, the patch is gone, and Windows falls back to its stock look or applies your theme in pieces. The light layers survive because they never touched system files: your dock, icons, cursors and wallpaper usually keep working. Only the deep layer breaks. Knowing which layer failed saves you from reinstalling everything.
Start simple. Restart the PC once - updates finish pending file work at boot, and a surprising number of half-applied themes settle after a clean start. Then open your theming settings and reapply the theme from scratch: select the default Windows theme first, then select your mac style theme again. If window borders return everywhere, you are done - the theme files were intact, only the selection was reset by the update.
If reapplying does nothing, the patch itself is gone. The order matters:
If the patcher reports that your Windows build is not supported yet, believe it. Wait for the patcher's update instead of forcing it - a forced patch on an unsupported build is how sign-in screens break.
Rare, but be ready. If the desktop will not load properly, boot into the recovery environment by interrupting startup three times, then use System Restore to return to the restore point you made before theming - or the automatic one Windows made before the update. This rolls back system files and the update's changes to them without touching your personal files. Once Windows is healthy, decide calmly whether to rebuild the look with updated tools or stay with the light layers only.
You cannot stop this cycle, but you can make it painless. Never disable Windows updates to protect a theme - updates carry security fixes, and a pretty desktop on an unpatched PC is a bad trade. Instead: create a fresh restore point before big feature updates; keep your theme files and tool installers in one folder so reapplying takes minutes; and after each feature update, expect to repatch the deep layer as routine maintenance. Many long-time themers eventually drop the deep layer entirely and keep the dock, icons and wallpaper - the 90 percent look that updates cannot break.
The complete transformation is shown live in the video, step by step, on a real laptop. Watch it before you start so you know exactly what each step does.
Watch Full VideoSmall monthly updates usually leave the deep layer alone. The big feature updates - the ones that change the Windows version - replace the most system files and are the usual breaking point. Plan on reapplying or repatching after those, roughly once or twice a year.
You can pause updates for a few weeks, but blocking them permanently is a security risk and this guide will not recommend it. The sane pattern is the one on this page: keep updates on, keep a fresh restore point, and treat reapplying the theme as light maintenance.
Exactly the deep layer. Your update replaced the patched theme files, so window borders and buttons reverted while the add-on tools kept running. Repatch with the latest patcher version and reapply the theme - your dock and icons need nothing.