Sometimes add-ins can conflict with Outlook. Starting Outlook in safe mode, which starts Outlook without add-ins loaded, can tell you if an add-in is the source of the problem.

When you enable an add-in, it adds custom commands and new features to Microsoft 365 programs that help increase your productivity. Because add-ins can be used by attackers to do harm to your computer, you can use add-in security settings to help protect yourself.

Learn Excel skills from beginner to advanced with video tutorials, templates, and tips from Microsoft Support.

Create a simple formula to multiply and divide in an Excel spreadsheet. You can multiply two or more numbers in one cell or multiply and divide numbers using cell references. All formulas in Excel begin with an equal sign (=).

Learn more about the Start menu, including how to find your files and get to your apps and programs.

Learn how to insert, change, or write an equation or formula in Microsoft Word.

Learn how to open MSConfig in Windows 10 using the taskbar search bar and access system configuration.

更新 Surface 设备和 Windows。 下载最新的驱动程序和固件更新，以使 Surface 设备保持最佳性能。

If you loved the free solitaire games from earlier versions of Windows, we've wrapped them all up in one convenient app, the Microsoft Solitaire Collection.

Add or edit hyperlinks to web sites, local files, email messages, or anchor points in your document.