Describes how to use the System File Checker tool to troubleshoot missing or corrupted system files in Windows.

Learn how to activate Windows using a product key or digital license, check your activation status, and link your Microsoft account.

Learn how to upgrade or downgrade your XBOX Game Pass or EA play subscription level.

Learn how to purchase Game Pass subscription on an XBOX console or a Windows device.

Learn how to add user accounts in Windows 10 and Windows 11. With an account, each person has separate files, browser favorites, and a private desktop.

Open Device Manager Select Start , enter device manager. Then, select Device Manager from the search results.

個人帳戶 公司帳戶 Microsoft 帳戶支援 如果您無法登入您的 Microsoft 帳戶，大部分的問題都可以由我們的登入助手工具找出。 該工具會要求您輸入嘗試登入的電子郵件地址或行動電話號碼，並檢查您提供的詳細資訊。 如果我們偵測到您的帳戶有問題，我們會告訴您需要採取哪些動作來解決問題。 如果 ...

The August 11, 2026 update for Windows 11, version 23H2 includes security and cumulative reliability improvements in .NET Framework 3.5 and 4.8.1. We recommend that you apply this update as part of your regular maintenance routines. Before you install this update, see the Prerequisites and Restart requirement sections. Summary Security Improvements CVE-2026-65810 - .NET Framework Elevation of ...

This cumulative update for Windows 11, version 25H2 and 24H2 (KB5120998), includes production-quality improvements. Announcements and messages This section provides key notifications related to this release, including announcements, change logs, and end-of-support notices. Windows Secure Boot certificate expiration Important: Secure Boot certificates used by most Windows devices expire ...

Learn what to do when you can't copy games and apps using network transfer on your Xbox console.