Assume that you use Microsoft SQL Server 2012 Service Pack 2 (SP2) or SQL Server 2014 AlwaysOn Availability Groups feature. When an availability group is moved from one server instance to another server instance because of a failover occurrence, you receive the following error message in SQL Server ERRORLOG on the server whose database is switching from the primary replica to a secondary replica:
System objects could not be updated in database '<database name>' because it is read-only
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Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.