What Happens If You Don't Activate Windows?

You can install Windows 10 or 11 and use it without activating — Microsoft lets you run an unactivated copy more or less indefinitely. But "more or less" hides a handful of real limitations. Here's precisely what you lose, what keeps working, and whether it's worth activating.

What still works (almost everything)

An unactivated Windows is surprisingly functional. You still get:

• Security updates and Windows Update — your PC stays patched and safe.
• All core apps and features — browsers, Office, games, drivers; everything runs normally.
• Full performance — Microsoft does not throttle or slow an unactivated PC. That's a persistent myth.

So nothing about your day-to-day speed or safety changes. The restrictions are cosmetic and convenience-related.

What you lose

• A permanent watermark in the bottom-right corner reading "Activate Windows — Go to Settings to activate Windows". See our guide on removing the watermark.
• Personalisation is locked. You can't change your wallpaper, accent colour, themes, lock screen, or Start/taskbar colours. The entire Personalisation page in Settings is greyed out.
• Occasional reminders nudging you to activate.

That's the full list. There's no data loss, no forced shutdowns, and no feature removal beyond personalisation.

Does it ever get worse over time?

No. An unactivated Windows behaves the same on day 1 and day 500 — the watermark and locked personalisation are the extent of it. Microsoft has kept it this way for years to let people evaluate Windows and to avoid bricking machines whose licence detection temporarily fails.

Should you activate anyway?

If the watermark and locked personalisation bother you — and for most people they do — activating is the clean fix and unlocks everything instantly. You have a few options:

• Use a licence you own — enter your product key or sign in with the Microsoft account holding your digital licence.
• Activate free with KMS — the volume-activation method Microsoft built for businesses. KMSPico applies it in one click, or follow the Windows 11 / Windows 10 guides.
• Do it manually from Command Prompt with the slmgr commands.

The bottom line

Running Windows unactivated is safe and fully functional — you only sacrifice the watermark-free desktop and personalisation. If those matter to you, activating takes under a minute and removes every limitation at once. Check your current status anytime with our activation status guide.