Change from a 32-bit version to a 64-bit version or vice versa. Activate Windows. Fix Bluetooth problems in Windows. Learn how to install, reinstall, or activate Microsoft 365 or Office 2019 on a PC or Mac.

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.

Install Microsoft 365 2019 or 2016 on a PC. Remember a one-time purchase version of Microsoft 365 is licensed for one install only. Depending on your browser, select Open file (in Edge or Internet Explorer), Setup (in Chrome), or Save File (in Firefox).

Error 0x8007045D or 8007045D occurs when you download your profile or an update or launch a game or app on your Xbox. Learn what to do if you see error code 0x8007045D or 8007045D when you try to download your Xbox profile or an update to your Xbox 360 console. Learn more.

You can use installation media (a USB flash drive or DVD) to install a new copy of Windows, perform a clean installation, or reinstall Windows. To create installation media, go to the software download website, where you'll find step-by-step instructions.

Follow the on-screen instructions to enter the sign-in info for your account. If you aren’t sure which email address is the right one to use for signing in, or if you can’t remember your password, see these resources for help: Find your Microsoft account email address.

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Learn how to redeem a gift card, code, or Office product key and spend your balance at Microsoft Store online, on Windows, or Xbox.

You can use a simple formula to sum numbers in a range (a group of cells), but the SUM function is easier to use when you’re working with more than a few numbers. For example =SUM (A2:A6) is less likely to have typing errors than =A2+A3+A4+A5+A6.

Get help and support, whether you're shopping now or need help with a past purchase. Contact Microsoft Support. Find solutions to common problems, or get help from a support agent.