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.

Open the Office folder in the virtual drive, and then select either the Setup32.exe to install the 32-bit version of Microsoft 365, or Setup64.exe to install the 64-bit version to begin the offline installation.

Double-click either the Setup32.exe to install the 32-bit version, or Setup64.exe to install the 64-bit version to begin the offline installation (If you're not sure which version is right for you, see Choose the 64-bit or 32-bit version of Office.)

To change from a 32-bit version to a 64-bit version or vice versa, you need to uninstall Microsoft 365 first (including any stand-alone Microsoft 365 apps you have such as Project of Visio). Once the uninstall is complete, sign in again to m365.cloud.microsoft/apps and select Install apps.

Download and install or reinstall Office 2021, Office 2019, or Office 2016. Important: Support for Office 2016 and Office 2019 ended on October 14, 2025 and there will be no extension and no extended security updates. All of your Office 2016 and Office 2019 apps will continue to function.

Use the Microsoft 365 setup troubleshooter to install Microsoft 365, Office 2021, Office 2019, or Office 2016 on your Windows PC. Select the button below to start the setup troubleshooter.

The installation file is typically named Autorun.exe or Setup.exe, but this may vary. If you're not sure, check the Readme file in the folder for instructions about how to run the installation.

Learn how to download and install apps you need from your Microsoft 365 business subscription.

When critical Windows system files are missing or corrupted, your operating system may begin to malfunction. Common symptoms include Windows features not working properly, system errors, or Windows becoming unresponsive or freezing.

Describes the new and improved features of Microsoft Windows Installer 4.5. The article also discusses the issues that are addressed from earlier versions of Windows Installer.