Research appears to show that when Microsoft Outlook 2016 CRM Add-In is installed, Outlook whilst acting as the Web Browser does not use Compatibility Mode which is required with the search function with Enterprise Vault 10.   A Fiddler Trace will show the request not being made using compatibility mode when this add-in is installed. 

With Microsoft Outlook 2016 CRM Add-In installed


Without Microsoft Outlook 2016 CRM Add-In installed

1:  Alter the Enterprise Vault Desktop policy to open search directly in IE. This avoids the use of Outlook and CRM.  (see the relevant Administrators Guide for details)
2: Remove Outlook 2016 CRM Add-In.
3:  Upgrade Enterprise Vault to EV 11.0.1 minimum and upgrade search features as this does not rely on the Compatibility View (see Enterprise Vault Compatibility Guide).

This issue occurred with the following combinations.

- Outlook 365 Build 7167.2060
- Enterprise Vault 11.X Outlook Add-In
- Enterprise Vault Server 10.0
- Microsoft 2016 CRM Outlook Add-In
- Enterprise Vault Desktop Policy set to open Search via Outlook

When the user selected the option to open search Outlook displays either a blank screen or the SMTP address of the user. The search webpage is never displayed.