"Incorrect username or password" on Secure Mail after Exchange Server upgrade to 2016 CU8

Since the exchange server was upgraded from Exchange 2016 to Exchange server 2016 CU8, users are facing 2 issues as below. 1. Existing users are unable to sync e-mail. 2. New users are unable to logon...

Secure Mail : Email Sync is not possible for a single user.

Exchange error : Seeing error for the user wd0283 Error - 4023,MSExchangeADAccess : locked out until 5/3/2017...