Try these checks in order:
- Verify the device is supported.
Microsoft 365 or Office won’t install on unsupported operating systems. For example, installs won’t succeed on Windows Vista or Windows XP.
- Download from the correct account page.
For Microsoft 365 for home, go to the Microsoft account Services & subscriptions page, then select Install premium M365 apps like Word, Excel, and PowerPoint on your device or Install.
- Choose language and version, then start the download.
In Download and Install Microsoft 365, select the preferred language and version, then select Install.
- Run the installer.
Open the Downloads folder, select OfficeSetup.exe, approve the User Account Control prompt with Yes, and wait for the Installing Office dialog to complete.
- If the install is very slow or does not start, check common blockers.
This can be caused by internet connection problems, firewall software, or antivirus software. If the connection is slow, use the offline installer.
- If the Install button does nothing, there was a known portal issue that has been fixed.
If this happened recently, try again from the portal.
- If an error message appears during install, select Learn More in the error dialog if available. If there is no link, use the Office install troubleshooting guidance.
- After installation, open an app such as Word from Start, accept the license agreement, and complete the Activation Wizard if it appears.
If the problem is specifically that the Install button is not working or the download never begins, the most relevant causes in the available guidance are unsupported OS, connection/firewall/antivirus issues, or the portal issue that has already been fixed.
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