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.

Your PC isn't working well and you recently installed an app. Restore from a system restore point. 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.

Report a scam. If you feel like you’ve been the target of a technical support scam, you can help Microsoft stop cybercriminals by reporting it. Learn more about avoiding technical support scams.

Follow these steps to reset your Microsoft account password. If you know the email address that you used to set up your Microsoft account (which is used to sign in to your Xbox profile), you can reset your password now: Go to Reset your password and enter your email address.

Check for Windows updates. Learn how to run Windows Update Troubleshooter to resolve errors downloading or installing Windows updates.

Calculation operators and order of operations. Create a simple formula to multiply and divide in an Excel spreadsheet. You can multiply two or more numbers in one cell or multiply and divide numbers using cell references. All formulas in Excel begin with an equal sign (=).

为何我的 Xbox 订阅付款被拒绝？. 使用 Microsoft 帐户余额进行购买. 你的 PayPal 帐户列出的国家/地区可能与支付选项的国家/地区不同。. 如果它们不匹配，则需要更新 PayPal 帐户或付款方式，或使用其他付款方式完成购买。. 若要添加另一种付款方式，请执行以下 ...

If a device is updating from Windows 10, version 1909 or an earlier version, this feature update enablement package cannot be manually installed. Instead, it is bundled and automatically included with the feature update to Windows 10, version 22H2.

If you need to reinstall Office, select the version you want to install and follow those steps: Microsoft 365, Office 2019, Office 2016, Office 2013, Office 2010, or Office 2007. How to uninstall Office automatically.

Get help and support, whether you're shopping now or need help with a past purchase. Contact Microsoft Support. Find solutions to common problems, or get help from a support agent.