Pre-installed Microsoft Store apps of Outlook may cause issues when installing the Outlook add-in. This installation may result in a similar error as seen in the screenshot below:

To remove the pre-installed Microsoft Store version of Office, run the script below in PowerShell:

Get-AppxPackage -name “Microsoft.Office.Desktop” | Remove-AppxPackage
Get-AppxProvisionedPackage -online | %{if ($_.packagename -match "Microsoft.Office.Desktop") {$_ | Remove-AppxProvisionedPackage -AllUsers}}

Ensure no registry keys from the older versions are still in place by following the steps below:

1. Open up Regedit.
2. Locate to HKEY_CLASSES_ROOT\TypeLib\{00062FFF-0000-0000-C000-000000000046}.
3. Make a backup of this registry location before making any changes.
4. Delete the version keys for any version of Microsoft Outlook that is not installed on the machine based on the version table provided below.