If your system is asking you for your BitLocker recovery key, the following information may help you locate your recovery key and understand why you're being asked to provide it. Important: Microsoft support is unable to provide, or recreate, a lost BitLocker recovery key.

It looks like this: PRODUCT KEY: XXXXX-XXXXX-XXXXX-XXXXX-XXXXX. Locate your product key for Windows 10 or Windows 11. Depending on how you got your copy of Windows 10 or Windows 11, you'll need either a 25-character product key or a digital license to activate it.

Activate Microsoft 365 or a non-subscription version of Office. When you start an Microsoft 365 app that's not activated, you'll be prompted to sign in to Microsoft 365. Be sure to sign in using the Microsoft account, or work or school account, that you used to buy or subscribe to Microsoft 365.

If you are unsure if your device meets the Windows 11 minimum system requirements and have Windows 10 already installed, you can download the PC Health Check app, which will assess eligibility and identify components of your device that don't meet the minimum requirements.

If you receive a message in Windows Security prompting you to update your security processor or TPM firmware, follow the steps in the "Recommended actions" section below. Note: In previous versions of Windows 10, Windows Security is called Windows Defender Security Center.

If you see a message that no changes or updates were necessary, you can try recovery options, or find out more about Outlook error codes and upgrade and installation error codes. Find troubleshooters. Fix-it tools aren’t used in Windows 10. Instead, use a troubleshooter to help solve problems with your PC.

Check for Windows updates. Learn how to update drivers in Windows using Device Manager to update or reinstall a driver.

Select the Dial icon to start your call. If you don't have Bluetooth available on your device (or if it's been turned off), you won't be able to make or receive calls on your PC. If you encounter issues while using the calling feature, these troubleshooting tips may help.

If you're having trouble installing updates, see Troubleshoot problems updating Windows. For answers to frequently asked questions, see Windows Update: FAQ. Learn about Windows service packs and download the latest updates for Windows 10 and Windows 8.1.

You suspect your device has been infected. Use installation media to reinstall Windows 11. Select one of the recovery options below and follow the steps to try to get things working again. If you've recently installed a Windows update, uninstall the update to try to resolve the issue.