FIX: Error when you edit models for some groups or users in MDS for SQL Server 2012 or SQL Server 2014

Applies to: SQL Server 2012 EnterpriseSQL Server 2012 DeveloperSQL Server 2012 Standard


Assume that you have deleted one or more entities in Master Data Services (MDS) for Microsoft SQL Server 2012 or SQL Server 2014. When you try to edit the model security for some groups or users in MDS, you receive the following error message:
An unknown error occurred.

Note When you enable MDS trace logging and reproduce the error, the following error message is found in the trace log:
An item with the same key has already been added.


The issue occurs because the attribute level security that belongs to the deleted entity is not removed accordingly.


The issue was first fixed in the following cumulative update of SQL Server.

Cumulative Update 1 for SQL Server 2014 SP1

Cumulative Update 6 for SQL Server 2014

Cumulative Update 4 for SQL Server 2012 SP2

Cumulative Update 13 for SQL Server 2012 SP1


To work around this issue, remove the corresponding attribute level security, or delete the attributes that are referenced in the group security. Then, delete the entity.


Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.