During our migration I ran into an error while sending e-mail to a mailbox that was just migrated.
#550 5.2.0 STOREDRV.Deliver: The Microsoft Exchange Information Store service reported an error. The following information should help identify the cause of this error: “MapiExceptionUnconfigured:16.18969:C4000000, 17.27161:0000000094000000000000000000000000000000, 255.23226:00000000, 255.27962:FE000000, 255.17082:1C010480, 0.26937:00000000, 4.21921:1C010480, 255.27962:FA000000, 255.1494:00000000, 255.26426:FE000000, 4.7588:0F010480, 4.6564:0F010480, 0.56333:0B004A66, 4.6372:05000780, 4.6276:05000780, 0.18684:02010480, 4.2199:78040000, 4.2770:05400080, 4.29385:1C010480, 4.8620:1C010480, 255.1750:0F010480, 0.26849:0F010480, 255.21817:1C010480, 0.26297:0F010480, 4.16585:1C010480, 0.32441:0F010480, 4.1706:1C010480, 0.24761:71040000, 4.20665:1C010480, 0.25785:0F010480, 4.29881:1C010480”. ##
If the account hasn’t properly replicated to all domain controllers, you might get this error. Forcing a replication using the Active Directory Sites and Services fixes the problem. This should trigger automatically, however replication issues might stop or slow this. Running a DCDiag and NETDiag will probably show you some problems.