A BitLocker recovery key is needed when BitLocker can’t automatically unlock an encrypted drive in Windows. This key, which is a 48-digit number, is used to regain access to the drive. You might be prompted for the BitLocker recovery key during startup, due to a security risk or hardware change:

If you can't sign in to your Outlook.com, Hotmail, Live, or MSN email account, or you're not sure how to sign in or sign out, here are some solutions.

If you're looking for product keys for Office, apps, games, and more, see Find your Microsoft downloads and product keys. Learn how to find a Windows product key for activation, and when you'll use a digital license instead.

Use this app to try to recover lost files that have been deleted from your local storage device (including internal drives, external drives, and USB devices) and can’t be restored from the Recycle Bin. Recovery on cloud storage and network file shares is not supported.

To use Microsoft 365 on your new device, you can activate Microsoft 365 as a 1-month trial of Microsoft 365 Family. You can also buy Microsoft 365 or a non-subscription version of Office, add Microsoft 365 to an existing Microsoft 365 subscription, or enter a product key from a new product key card.

If you can't find a file on your computer or you accidently modified or deleted a file, you can restore it from a backup (if you're using Windows backup) or you can try to restore it from a previous version. Previous versions are copies of files and folders that Windows automatically saves as part of a restore point.

If some Windows functions aren't working or Windows crashes, use the System File Checker to scan Windows and restore your files. Though the steps below might look complicated at first glance, just follow them in order, step-by-step, and we’ll try to get you back on track.

You can start a scan for malware any time you like. Note: Microsoft Defender currently offers anti-malware on Windows, Android, and macOS. From the Microsoft Defender dashboard. If you want a deeper scan, instead of selecting Quick scan in step 3, select Scan options and choose the type of scan you want.

Installation media, such as a USB flash drive, can be used to install a new copy of Windows, perform a clean installation of Windows, or reinstall Windows. To create installation media, go to the software download website, where step-by-step instructions can be found.

Hotmail is now Outlook.com. Learn how to sign in to access your Outlook.com, Hotmail, Live, or MSN email account.