Office 2016 & protected view

[ITGURU]

Hi

I've deployed Office 2016 on windows 10 on some computers for testing.

I've managed to add local network drives as exclusion from protected view, so they can be opened rather than it saying the file is corrupt and unreadable (which of course isn't true).

 

However, when users open office attachments from OWA webmail it is blocking those. I have an internal exchange server and I have added the url without the https:// to the trusted locations but when trying to open the attachments it says they are corrupt and unreadable still.

 

Please could I have some advise on what GPO settings are required to allow attachments to open from OWA in office.

 

Thanks.