We have a SharePoint Server 2016 farm and configured AD FS authentication via SAML. Email address is used as a user identifier.
1) , if we choose 'Accept email messages from any sender', we do receive email attachments on the document library
2) If we choose 'Accept email messaged based on document library permissions', attachment are no more received by the document library.
Now, here what I found in the ULS logs :
No match in user info list. Input : email@example.com
And the same user on the user info list has the following entry :
Account : i:05.t|trustedIdentityProviderfirstname.lastname@example.org
In this context, how to tell SharePoint that email@example.com is the same user as i:05.t|trustedIdentityProviderfirstname.lastname@example.org ?
[Update 1] @Trevor : Here are the synced attributes