Just letting anyone who may be looking for a resolution to this error: "Failed to authorize Office 365 email access: Authorization failed with error access_denied AADSTS65004: User declined to consent to access the app."
We were on 12.7.7 and kept getting this error. We have two installs of WHD and the one on 12.7.9 worked fine. We upgraded the 12.7.7 to 12.7.9 and it instantly worked. Solarwinds tech support doesn't bother to let you know that Oath doesn't work on 12.7.7 and lets you waste your day figuring this out on your own. So I hope this post saves someone some time.