Learn how to recognize Internet connection problems and help improve your computer's online performance.

How to use the COUNTIFS function in Excel to apply criteria to cells, across multiple ranges, and count the number of times all criteria are met.

Learn how to open, navigate, and troubleshoot File Explorer in Windows, with answers to common questions and support assistance.

Find app notifications from the taskbar in Windows 11, and in Windows 10, use quick actions to change settings quickly as well.

You can use Microsoft Office Excel to create and edit connections to external data sources that are stored in a workbook or in a connection file. By using the Workbook Connections dialog box, you can easily manage these connections, including creating, editing, and deleting them. Data in an Excel workbook can come from two different locations.

Learn how to restore files that have been permanently deleted and are no longer in the recycle bin on Windows 10.

Learn how to check your Xbox purchase history. If you compared your bank statement to your purchase history and others’ purchase histories and still can’t reconcile the charge, note that you can investigate a charge from Microsoft on any card you own.

查找有关 Windows 操作系统的帮助和操作方法文章。 获取对 Windows 的支持，并了解安装、更新、隐私、安全等方面的信息。

Contact Microsoft Support. Find solutions to common problems, or get help from a support agent.

Get troubleshooting tips if you run into problems downloading, installing, or updating Microsoft Edge.