Download and install or reinstall Microsoft 365 or Office 2021 on a PC or Mac. Set up Office apps and email on a mobile device. Small business help and learning. Learn how to download and install apps you need from your Microsoft 365 business subscription.

Some Office 2019, Office 2016, and Office 2013 products come with a product key. If yours did, before installing Microsoft 365 for the first time, sign in with an existing or new Microsoft account and enter your product key at office.com/setup. Redeeming your key is what links your account with Microsoft 365 so you only have to do this once.

Installing Windows 11 on devices that don't meet minimum system requirements. If you changed your hardware in order to upgrade to Windows 11 and the system is not recognizing the change in a timely manner, this article explains how to initiate the assessment manually.

Change from a 32-bit version to a 64-bit version or vice versa. Activate Windows. Fix Bluetooth problems in Windows. Learn how to install, reinstall, or activate Microsoft 365 or Office 2019 on a PC or Mac.

Sign in to SharePoint. SharePoint is a browser-based app that you connect to through your web browser, like so: Go to office.com, and sign in to your work or school account. In the upper left corner of the window, select the app launcher > All apps > SharePoint.

下载并安装或重新安装 Office 2019、Office 2016 或 Office 2013. 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 ...

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Once the Windows 11 upgrade has been tested and validated for your specific PC, Windows Update will indicate that it's ready for installation. To check if Windows 11 is ready for your device, go to Start > Settings > Update & Security > Windows Update and select Check for updates.

If an existing Windows 10 device is running a currently supported version of Windows 10 and meets the minimum hardware specifications to run Windows 11, it can be upgraded to Windows 11. Specific timing for upgrade rollout varies by device and certain features require specific hardware.

If you get an error code while downloading and installing Windows updates, the Update Troubleshooter can help resolve the problem. Select Start > Settings > System > Troubleshoot > Other troubleshooters. Next, under Most frequent, select Windows Update > Run.