Tackling the Error 0x80070643: Office 2021 Installation Fail

Follow these practical steps to fix the error code 0x80070643 and successfully install Office 2021:

1. Give your computer a fresh start by rebooting and then attempt the Office 2021 installation once more.
2. Temporarily turn off any antivirus programmes and try the installation of Office 2021 again.
3. Ensure your Windows operating system is up to date; if it’s not, update it and then try the Office 2021 installation again.
4. Remove any old versions of Office that may interfere with the new Office 2021 installation.
5. Utilize the Microsoft Office Installation Troubleshooter to identify and resolve any installation problems.