See how to find things you've downloaded on your PC.

How to use the SUMIF function in Excel to add the values in a range that meet criteria that you specify.

了解在 Windows 中查找 BitLocker 恢复密钥的不同方法，并了解如何在系统上激活 BitLocker。

Learn how to install the latest version of DirectX to enable games and multimedia applications on your system.

Get the steps for showing your favorites bar in Microsoft Edge and Internet Explorer 11.

If you cannot open your Outlook data file or suspect that the file is damaged, use the Inbox Repair tool (scanpst.exe) to repair errors in the file.

How to lock cells in Excel to protect your data. You can also unlock a range of cells and grant permissions to others to edit.

Learn how to update your security processor or TPM firmware to protect Windows 10 and your device from attacks by malicious software.

Open and edit PDF content in Word. To edit a PDF, open it in Word. This works best with PDFs that are mostly text.

This topic offers troubleshooting tips if you don't have the Teams Meeting add-in in Outlook for Windows. The add-in helps you set up a Teams meeting from your Outlook email.