"Some implicit and explicit data type conversions are not supported
when you are converting the data type of one SQL Server object to
another. For example, an nchar value cannot be converted to an image
value. An nchar can only be converted to binary by using explicit
conversion, an implicit conversion to binary is not supported.
However, an nchar can be explicitly or implicitly converted to
nvarchar."
http://msdn.microsoft.com/en-us/library/ms191530.aspx
I thought this might be useful. Perhaps it is necessary to use
explicit conversion for datatypes that do not implicitly convert.
Refactoring the model worked, but it would be nice to not have to
worry about this.
All the best,
Cam