You may need to make sure that your SQL server is upgraded to Service Pack 2. There are several compatibility issues with RTM version 1.0 and SQL Server 2008R2.
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The following table lists the major releases of SQL Server 2008 R2.
Release Product version
SQL Server 2008 R2 Service Pack 2 10.50.4000.0
SQL Server 2008 R2 Service Pack 1 10.50.2500.0
SQL Server 2008 R2 RTM 10.50.1600.1
Microsoft article on server version
Connect to an instance of SQL Server and run the following query:
Select @@version