I am unable to find a way to disable the Microsoft Outlook search option "show most relevant search results on top" via a systematic / automated approach so that I can deploy this to all of our users.
The setting is located via in the GUI via the following:
"File" -> "Options" -> "Search" -> "Show most relevant search results on top".
What I have tried so far:
Group Policy
The most recent ADMX for configuring Microsoft 365 / Office etc does not seem to have an option to configure this:
Registry
After inspecting the applications modifications to the registry via "Process Monitor" when setting the option via the GUI, I have then modified the following key to 0
of which had no impact.
Computer\HKEY_CURRENT_USER\SOFTWARE\Microsoft\Office\16.0\Outlook\Search\SearchTopResults
Adding this key to the following location as per Christy's answer below also has no effect to outlook:
Computer\HKEY_CURRENT_USER\SOFTWARE\Policies\Microsoft\office\16.0\outlook\Search\SearchTopResults
Office configuration Tool
The office configuration tool also does not appear to show any possibility of disabling this option under "Application Prferences":
https://config.office.com/deploymentsettings
PS - the environment that this being tested in is connected to active directory with policies applied through an existing "group policy" deployment.
If anyone is able to give any insight on how to do this it would be greatly appreciated.