什么是安全启动？ 安全启动是统一可扩展固件接口中的一项安全功能， (基于 UEFI) 的固件，可帮助确保只有受信任的软件在设备的启动 (启动) 序列中运行。 它的工作原理是针对存储在设备固件中的一组受信任的数字证书 (（也称为证书颁发机构或 CA) ）验证预启动软件的数字签名。 作为行业标准 ...

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Applies to: Windows Server 2019 This security update includes fixes and quality improvements that are part of the following update: November 11, 2025—KB5068791 (OS Build 17763.8027) The following is a summary of the issues that this update addresses when you install this update. The bold text within the brackets indicates the item or area of the change we are documenting. [PowerShell 5.1 ...

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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Alpha Ring (2506.250612-1215) Hey Xbox Insiders! We are releasing a new Xbox Update Preview to the Alpha ring today. Continue reading below to learn all about what's included with this update.

本文介绍了启用了 Windows 8.1、 Windows RT 8.1、 Windows Server 2012 R2、 Windows 8，Windows RT，Windows Server 2012，Windows 7 和 Windows Server 2008 R2 中的 根证书的 Windows 程序 的紧急更新的更新。应用此更新之前，请参阅更多 有关此更新，请查看本文中的 系统必备组件。 关于此更新 Windows 根证书程序允许受信任的根 ...

Delta Ring (2405.240501-1900) Hey Xbox Insiders! We are releasing a new Xbox Update Preview to the Delta ring today. Continue reading below to learn all about what's included with this update.

Follow these steps to make a purchase: Select the Start button, then select Settings > System > Activation . Then select Go to Store to go to the Microsoft Store app where you can purchase a Windows 11 digital license. Open Activation settings Need more help? If you need additional help reactivating Windows on your device, contact customer support.

Don't forget to include your license ID or agreement number, your contact phone number & email address so we can contact you. If you already have a volume licensing support case number, you may be in a location where you can phone the Volume Licensing support team.