If you want to open data in Outlook directly for the Cleanup Report you will need to update the end-users computer's Registry. (Enterprise edition only)
First, change the settings to Open In the desktop app
This will change the link structure in the cleanup report so chrome will try to open the default mail client with the mail id. To make this work you need to update the
Use Registry edit to update the Registry
To update the registry use the RegEdit below. Be aware the path below should be modified so it matches the end-uses installation
\Program Files\\Microsoft Office\\root\\Office16\\OUTLOOK.EXE
To enable this please run the RegEdit below on end-user computers.
_________________________________________________
Windows Registry Editor Version 5.00
[HKEY_LOCAL_MACHINE\SOFTWARE\Classes\outlook]
@="URL:Outlook Folders"
"URL Protocol"=""
[HKEY_LOCAL_MACHINE\SOFTWARE\Classes\outlook\DefaultIcon]
@="C:\\Program Files\\Microsoft Office\\root\\Office16\\OUTLOOK.EXE"
[HKEY_LOCAL_MACHINE\SOFTWARE\Classes\outlook\shell]
@=""
[HKEY_LOCAL_MACHINE\SOFTWARE\Classes\outlook\shell\open]
@=""
[HKEY_LOCAL_MACHINE\SOFTWARE\Classes\outlook\shell\open\command]
@="\"C:\\Program Files\\Microsoft Office\\root\\Office16\\OUTLOOK.EXE\" /select \"%1\""
To change multiple end-users Registry you can use a GPP as described in the blog below.
(http://woshub.com/how-to-create-modify-and-delete-registry-keys-using-gpo/)