You can insert a drop-down list of valid entries (also called a drop-down menu or drop-down box) in Excel to make data entry easier, or to limit entries to certain items that you define.

Create Outlook Data Files (.pst) on your computer to save Outlook items by account, project, or to archive older items.

Learn how to delete and restore files in OneDrive. Recover deleted files or folders from the OneDrive recycle bin.

Calculate the difference between two dates. Use the DATEDIF function when you want to calculate the difference between two dates. First put a start date in a cell, and an end date in another. Then type a formula like one of the following. Warning: If the Start_date is greater than the End_date, the result will be #NUM!.

Microsoft Teams includes the Outlook add-in, which lets you create new Teams meetings directly from Outlook. You can also view, accept, or join meetings in either app. Notes: Currently, you can schedule Teams meetings from Outlook, but not choose a channel to have them in. The Outlook add-in doesn't currently support creating meetings in Teams ...

Learn how to reset or change your Microsoft account password. Get help with a forgotten Microsoft account password.

See how to install Project 2013 and 2016 and Project Pro for Office 365.

Learn how to view your PC information on Windows with Microsoft Support's step-by-step guide.

First, try checking your hardware. Unplug USB cables and wait for a little while for the device driver to be unloaded by Windows, and then plug the device back in. Try using a different USB port on your PC. If you use a USB hub between the device and the PC, make sure the hub has power. If it’s still not working, try removing the USB hub and ...

Learn how to remove malware from your PC. Use Microsoft Defender Antivirus in Windows 10 or Windows 11 to scan your PC for malware, viruses, or other threats.