Update regarding the following issue. I found that one user is running Outlook 2016 Version 1805 (Build 9330.2124 Click-to-Run) and the other user is running Outlook 2016 Version 1806 (Build 10228.20021 Click-to-Run). I requested that each user go through the procedure to Add Account. The user running Version 1805 is now able to decrypt and read the encrypted messages from Company A. The latter user did the same but is still having an issue decrypting and reading encrypted messages from Company A.
Encrypted messages are sent from company A who has an O365 tenant with OMEv2 enabled to company B who has an O365 tenant.. Users at Company B are running Outlook 2016 Version 1805 (Build 9330.2124 Click-to-Run). Most users can decrypt and read encrypted messages from Company A without issues but two users ran into issues opening encrypted messages from Company A.. When they attempt to open an encrypted message they receive the following: "The logged in users could not be authenticated. Please check your credentials or try signing out and signing back in". They appear to be logged in with there Azure AD account but cannot decrypt and read the encrypted messages from Company A. I tried having one user "Add Account" and "Sign In" but it did not resolve the issue. Is this a bug. How can I troubleshoot?