We have a program that is using the Symbol.Barcode API from Motorola EMDK for .NET. When we run the program on older handcomputers and a MC55A it works without any problems but when we run it on our MC55 (a little older then the MC55A) we get this OperationFailureException

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 the second time the code line this.myReader.Actions.Enable(); is executed. We can’t figure out what the problem is. So what is the cause of this problem? And how do we fix this?