You can connect Mozilla Thunderbird 8.0 to your email account using POP3 or IMAP4 connectivity. These instructions apply to Windows and Mac. Note: This topic applies to Office 365 operated by 21Vianet in China.

There are two ways to get apps from Microsoft Store: Select Start , and select Microsoft Store. From the taskbar, select the Microsoft Store icon.

First, you'll need to download the troubleshooter. Download troubleshooter. If you see the File Download box when you start downloading, select Run or Open. The troubleshooter provides steps for you to follow. If a program isn't listed in the uninstall options, you'll be asked for that program's product code.

Go to microsoft365.com and sign in with your Microsoft 365 account. Select Install and more, and then select Install Microsoft 365 apps. Select Install Office, and then open the OfficeSetup.exe file that downloads to your computer.

To install a standalone version of classic Outlook for Windows, select your language from the dropdown, and then select Download. Follow the prompts to complete the installation. Which language do you need? Tip: You can also try installing classic Outlook from the Microsoft Store.

Use the System File Checker tool to repair missing or corrupted system files. When critical Windows system files are missing or corrupted, some Windows features may stop working correctly or Windows may stop responding altogether.

Find how-to articles, videos, and training for Microsoft Copilot, Microsoft 365, Windows, Surface, and more.

To complete the installation and activation steps, follow the prompts in the following install and activation sections. Tip: Don't see an install option after signing in? There could be an issue with your account. Select Need help? from above and review the solutions under Account questions.

There are three steps you can take to try to get Outlook working again. Occasionally, classic Outlook tries to run a process in the background. Auto-archive, sending and receiving a very large attachment, or running some of the other mailbox tools can all be done in the background.

Download the application from the Microsoft Store, or just open the Windows Mail and Calendar app, and then select Open Outlook from the dialog box that opens. Users of classic Outlook can select the Try the new Outlook toggle in the upper corner of the screen.