About digital signatures and certificates in Office, and buying a digital certificate from a certificate authority or create your own.

Learn how to use the Gaming Services Repair Tool to troubleshoot installation and update issues with Gaming Services on PC.

A popular tactic of criminals is the "fake order" scam. The way it works is that you get a message, usually in email or text, that appears to be a routine confirmation for an order. Of course, you never ordered whatever product or service it's confirming. The message looks common enough, and it says that money will be charged to your credit card or withdrawn from your bank account for the ...

Certificate authority (CA) A certificate authority is an entity similar to a notary public. It issues digital certificates, signs certificates to verify their validity and tracks which certificates have been revoked or have expired. Top of Page Digital signature assurances The following terms and definitions show what assurances are provided by digital signatures. Authenticity The signer is ...

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Microsoft正在对永久许可证的激活体验进行现代化改造。 从 2025 年 12 月 3 日起，传统的基于电话的产品激活自动化过程已从电话转移到在线。 客户将改用产品激活门户： 产品激活门户 新的数字工作流提供更安全、更可靠且用户友好的激活体验，并有助于防止欺诈。 虽然该过程已更新，但脱机激活 ...

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Starting in April 2026, social clubs on Xbox will no longer be available. Learn about alternatives for connecting, sharing content, and coordinating with other players.

如果所购买的 Office 或 Microsoft 365 随附有产品密钥，请在你的产品所对应的下列网站中输入产品密钥。 输入密钥后，便可以下载并安装 Office，或可以续订 Microsoft 365 订阅。

摘要 Email签名在业务通信中创造专业一致性，并确保收件人在每封邮件中都有你的联系信息。 在Outlook 中，可以设置多个签名， (内部与外部、个人与业务) 的不同用途，并选择是自动将其包含在新的电子邮件、答复还是转发中。 签名可以包括文本、链接、图片和图像 (，例如手写签名或徽标 ...