Check the class attributes. Check whether the contract class have [DataContractAttribute] attribute if not write there and compile and cil your objects.
The above error comes due to missing class attributes.
Hi Sanjay, it seems that some of your service operations accepts or returns a class that isn't a data contract. You can just use any class, it must be possible to serialize it to a string, transfer it over network and deserialized it in another applications. Data contract classes can do it. Maybe it was your intention and you merely forgot the attribute.
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