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Question

I have this query and I get the error in this function:

var accounts = from account in context.Accounts
               from guranteer in account.Gurantors
           


        

Answer 1

This can happen if you execute a query while iterating over the results from another query. It is not clear from your example where this happens because the example is not complete.

One thing that can cause this is lazy loading triggered when iterating over the results of some query.

This can be easily solved by allowing MARS in your connection string. Add MultipleActiveResultSets=true to the provider part of your connection string (where Data Source, Initial Catalog, etc. are specified).