I ran into this exception on a user defined list. The problem was with the custom fields that were defined in the schema.xml of the list template. It was done in the following way:
<Field … Type=”Text” DisplayName=”CustomField1″ ” ColName=”nvarchar3” />
<Field … Type=”Text” DisplayName=”CustomField1″ ” ColName=”nvarchar3” />
The problem is the these two different fields link to the same ColName. So if you run into this exception double check that the values of ColName attribute are unique through the list.