Getting Error message from linq to entity query.
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I keep receiving the error
"LINQ to Entities does not recognize the method 'System.String get_Item(Int32)' method, and this method cannot be translated into a store expression"
on the following line in my code

var Reviewer = repository.reviewers.FirstOrDefault(t => t.ReviewerName == formCollection[3]);

formCollection[3] is a string returned from a drop down I have contained within a form. The query seems to work O.K. until it returns the value from the database. What can I do to fix this?