If some Windows functions aren't working or Windows crashes, use the System File Checker to scan Windows and restore your files. Though the steps below might look complicated at first glance, just follow them in order, step-by-step, and we’ll try to get you back on track. Run the System File Checker tool (SFC.exe)

See I forgot the account I use with Office. From the Overview page, select Office apps and on that page, find the Microsoft 365 product you want to install and select Install. To install Microsoft 365 in a different language, or to install the 64-bit version, use the dropdown to find more options.

If you recently made any changes to your hardware and want to see if your computer now meets the requirements for Windows 11, the easiest way to do that is with the PC Health Check app: If you haven't yet, install the PC Health Check app here.

The VLOOKUP and HLOOKUP functions, together with INDEX and MATCH,  are some of the most useful functions in Excel. Note: The Lookup Wizard feature is no longer available in Excel. Here's an example of how to use VLOOKUP. =VLOOKUP (B2,C2:E7,3,TRUE) In this example, B2 is the first argument —an element of data that the function needs to work.

Sign in to SharePoint. SharePoint is a browser-based app that you connect to through your web browser, like so: Go to office.com, and sign in to your work or school account. In the upper left corner of the window, select the app launcher > All apps > SharePoint.

An app for scanning files, such as Windows Scan, available for free from Microsoft Store. The Windows Scan app can help you scan pictures or documents and save them to your PC as JPEG, bitmap, or PNG files. For more info, see Install and use a scanner in Windows. Get Windows Scan.

Windows 11 in S mode is designed for security and performance, exclusively running apps from the Microsoft Store. If you want to install an app that isn't available in the Microsoft Store, you'll need to switch out of S mode. Windows 11 in S mode is only available in the Windows 11 Home edition.

Find out how to submit a request for a refund for a purchase of digital Xbox content.

For those devices, you can sign in with an app password instead. An app password is a long, randomly generated password that you provide only once instead of your regular password when signing in to an app or device that doesn't support two-step verification.

Help for admins of small businesses. Contact Microsoft Support. Find solutions to common problems, or get help from a support agent.