New Outlook - Unable to change "Always Open with System Viewer" setting

[djohnsonASE]

Hello,

When I first downloaded a pdf attachment in the New Outlook, I accidentally clicked the option to "Always Open with System Viewer". However, after a very exhaustive search, I cannot find a way to change this setting back - neither in settings or in the attachment download drop-down menu. I would like to be able to download pdf attachments without automatically opening them. Anyone know how I can clear or reverse this setting? This issue is quite annoying as it often opens a new instance of my default pdf app every time I download a pdf attachment. A setting similar to the option in Microsoft Edge under Download settings (see screenshot below) would be great, but I'm open to any/all suggestions, even modifying the registry if I have to.

Thanks in advance!

[#2]

Jumping on this because I as well have this issue.  It's driving me crazy and I'm going to have to go back to the old outlook if this doesn't get resolved.

[#3]

@ryshultz do you know how to revert back to old Outlook?  Anyone?  It gave me the opportunity to change, and then told me it doesn't support my server!  (BTinternet)