Learn how to fix Outlook.com email sync issues if you can't receive or send messages.

Learn how to import Google Gmail to Outlook and your Office 365 mailbox. You can also import Gmail contacts to Outlook, and see your Google Calendar in Outlook.

Describes how to troubleshoot problems that occur when you install, uninstall, or upgrade a program on a Windows-based computer by using Windows Installer.

The Planner app in Microsoft Teams brings together all your tasks and plans across the Microsoft 365 ecosystem in a single convenient location. It helps you manage tasks more efficiently for individual plans and team initiatives, as well as larger scale projects that are aligned to goals and key strategic objectives.

Learn how to change the settings that enable or disable macros in Excel, and more. Change the macro security settings to control which macros run when you open a workbook.

Training: In Microsoft PowerPoint, you can record your presentation, narration, and animation timings to give it a professional and polished feel. Watch this video to learn how.

Access, download, or run the Surface app and the Surface Diagnostic Toolkit to help find and solve Surface problems.

Learn how to set up a connection to a proxy server on your Windows PC.

Save your Office file as a PDF without needing additional software or add-ins.

即使已开启其他防火墙，开启 Microsoft Defender 防火墙也很重要。 它保护你免遭未经授权的访问。 若要打开或关闭 Microsoft Defender 防火墙，请执行以下操作：