Entity Framework: There is already an open DataReader associated with this Command which must be closed first.

EntityCommandExecutionException {“There is already an open DataReader associated with this Command which must be closed first.”}

You get this error when your DataContext tries to retrieve a collection of objects from the database and then subsequently tries to write to an object in the same connection.

For 99% of the cases, you will be able to resolve this issue by wrapping your DataContext in a using block:

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What do you think?