Learn how to access your Outlook.com, Hotmail, Live, or MSN email account with your Microsoft Account username and password. Find solutions for common sign-in problems, troubleshooters, and tips.

Learn how to locate your 48-digit BitLocker recovery key when you need to unlock an encrypted drive in Windows. The key can be attached to your Microsoft account, work or school account, printout, or USB flash drive.

Learn how to use a USB flash drive or DVD to install or reinstall Windows 10, 8.1, 7, or 11. Find the software download website, product key, and recovery options.

Find out how to download and install Office 2016 on your PC or Mac, or reinstall it if you already have a product key. Learn how to activate Office 2016 and troubleshoot common issues.

Learn how to fix errors in your Outlook mail profile that prevent you from connecting to your email. Follow the steps to repair your profile, run Windows Update, or use the Microsoft Support and Recovery Assistant.

Learn how to download and install Microsoft 365 or Office 2021 on a PC or Mac with a Microsoft account, work or school account. Find out how to activate, change versions, and troubleshoot common issues.

Learn where to enter your product key for different versions of Office or Microsoft 365, and how to install or reinstall Office after redemption. Find tips for troubleshooting product key issues and contacting support.

Learn how to use Microsoft Defender to check your device for viruses or malware on Windows, Android, or Mac. Find out the signs of infection, the types of scans, and how to run Microsoft Defender Offline for a deeper scan.

如果这是你第一次安装 Microsoft 365，则可能需要先执行一些设置步骤。展开下面的 “了解详细信息”部分。 但是如果是重新安装 Microsoft 365，且已兑换了产品密钥并拥有与 Microsoft 365 相关联的帐户，请转到“登录并安装 Office”的部分。

Find the POP, IMAP, or SMTP settings for your Outlook.com account to add it to Outlook or another mail app. Learn how to enable POP or IMAP access, troubleshoot connection errors, and get help from Microsoft.