Operation is not valid due to the current state of the object.

An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

System.Data.Linq.ForeignKeyReferenceAlreadyHasValueException: Operation is not valid due to the current state of the object.

Line 871:				if (this._Login_Detail.HasLoadedOrAssignedValue)
Line 872:				{
Line 873:					throw new System.Data.Linq.ForeignKeyReferenceAlreadyHasValueException();
Line 874:				}
Line 875:				this.Onlog_id_fkChanging(value);