Installation FAQ

Find requirements and fixes for common AtlasOS installation problems.

What do I need before installing?

  • Windows 11: Pro, Pro for Workstations, or Enterprise. Atlas does not support Home; upgrade with a product key before installing
  • 64-bit CPU (x64) or ARM CPU (ARM64): Use the matching Windows ISO for your architecture (how to check)
  • A backup of all important data: Atlas installs by reinstalling Windows; your current setup will be replaced
  • USB drive: Only needed for the ISO injection method. The Playbook method (recommended) installs directly from Windows with no USB required

For a full checklist, see Installation requirements.

Who is Atlas designed for?

Atlas is for enthusiasts who want more privacy, performance, and control over Windows. Do not install Atlas if:

  • You don’t fully own the computer
  • You’re not comfortable troubleshooting Windows issues
  • You’re not willing to reinstall Windows to remove Atlas

Can I install on a virtual machine?

Yes. Use the Playbook method. Some optimizations may not apply in a VM, but it works for testing.

Where is the Atlas ISO file?

Atlas doesn’t distribute a modified ISO. You use a stock Windows ISO and AME Beta to install Atlas. See Where is the Atlas ISO file? for details.

How long does installation take?

About 30-45 minutes, depending on your hardware and internet speed.

What if I get a BitLocker error?

If you see “Make sure BitLocker Drive Encryption is suspended”:

  1. Boot back into your original Windows
  2. Control Panel then BitLocker Drive Encryption
  3. Click Suspend protection for your system drive
  4. Restart and continue installation

Tip

The drive stays encrypted; you can resume BitLocker after installation.

What if Windows Update fails?

  1. Check your internet connection
  2. Run Windows Update Troubleshooter (Settings then System then Troubleshoot)
  3. Restart and try again

What was removed from Windows?

Atlas disables many components for performance and privacy. See the Atlas source code for exact changes. Key removals:

  • Smart App Control - Permanently disabled (requires reinstall to restore)
  • Telemetry - Toggleable in Atlas folder
  • Microsoft account syncing, ads, tips - Disabled
  • Apps uninstalled by default: OneDrive (if not set up), Edge (optional), Steps Recorder, modern Media Player/Films & TV, and various Store apps (Mail, Weather, News, etc.). Most can be reinstalled from the Microsoft Store.

Why disconnect internet during Windows installation?

Disconnect the internet to stop Windows Setup from installing drivers and updates before you choose how to manage them.

What if installation fails?

Common causes:

  • Not enough disk space (need at least 64GB free)
  • Corrupted ISO file (re-download)
  • BitLocker enabled (suspend it first)
  • Hardware incompatibility (check Windows 11 requirements)

How do I remove Windows.old?

  1. Settings then System then Storage
  2. Click Temporary files
  3. Select Previous version of Windows then Remove files

Tip

Remove this folder only after you recover every file you need from the previous installation.

What should I do after installation?

After installation:

How do I uninstall AtlasOS?

Atlas requires a full Windows reinstall to uninstall. See our Reverting Atlas guide for step-by-step instructions.