PC または Mac に Microsoft 365 または Office 2019 をインストール、再インストール、またはライセンス認証する方法について説明します。

Discover how to earn Microsoft Rewards points through various activities and redeem them for exciting rewards.

Learn how to use antivirus protection in Windows Security to protect your Windows PC against malware, viruses, and other threats.

Get troubleshooting steps for when you can't sign in to the Xbox app.

通过 Skype for Business，你可轻松与世界各地的同事和业务合作伙伴进行联系和协作： 启动即时消息对话和语音或视频呼叫。

Training: Sync files in Microsoft 365 or SharePoint document libraries so they’re always available on your computer even when you’re offline.

Contact Microsoft Office Support for assistance with Microsoft 365, Office, Windows, Xbox, Surface products and more.

Sign in to account.microsoft.com, then select Order History on your Rewards page.

Learn how to access Windows device security settings in Windows Security to help protect your device from malicious software.

我的产品密钥不起作用. 如果 Office 产品密钥不起作用，或已停止工作，应与卖家联系，申请退款。 如果产品密钥是独立于软件购买的，则很可能是被盗的产品密钥，或者是以欺骗方式获得随后阻止使用的产品密钥。