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 why it's important to have a backup, and how Windows Backup can help you keep your files and settings safe.

Find out how to install the latest driver for your printer. If you recently upgraded Windows, your printer driver might need to be reinstalled.

Learn how to download, install, and configure additional language packs for your version of Windows.

Learn how to use InPrivate browsing in Microsoft Edge if you don't want your browsing data saved on your PC.

If you need help with Outlook.com, you can read our self-help content, or get support via email.

Learn how to change Microsoft account email address or phone number using aliases to sign into your Microsoft account.

Find and open File Explorer in Windows 10 and Windows 11, and customize Quick access by pinning and removing files and folders.

Using the new Microsoft Teams, you can now be logged into multiple work, school, and personal accounts on the Windows desktop app. Easily switch back and forth between organizations, including guest organizations. See and change your notification settings for your various accounts.

How to use the SUMIFS function in Excel, one of Excel’s math and trig functions, to add arguments that meet multiple criteria.