Outlook 2016 constantly prompts for password on first start with Azure AD / Office 365

Hey folks,

After many years since my last, I’m doing yet another Office 365 migration. I’m fortunate that everyone is on Outlook 2016 and Windows 10… not too much legacy baggage there. This time around, I’m using Azure AD Sync + Pass-through authentication. The last migration I did, this functionality wasn’t even available.. I had to use Okta and then eventually OneLogin to accomplish my goals.

At first, everything seemed to be working fine, no password prompts using OWA with IE/Edge and Chrome. This was all good for me, since I tend to use OWS 100% when I’m on Office 365.

SADLY: Outlook itself was prompting for a password on first start / launch. The dreaded Outlook credential begging window in all its glory:

I went back through the manuals, looked at all of my Azure AD config… couldn’t figure it out. In my desperation, I ran across this blog: Jaap Wesselius: Single Sign-On and Azure AD Connect Pass-Through Authentication

The key step I missed (or didn’t know about?):

Set-OrganizationConfig -OAuth2ClientProfileEnabled:$true

After enabling that, I was immediately in business and no more password prompting from Outlook! Hopefully this helps someone, because this is yet another dark alley I see a lot of people struggling through.

Til next time…