How to mole System.dll

Problem: I get “no suitable method found to override” errors when I mole system.dll. Solution: Modify the System.moles file in your project and exclude everything except the types you are trying to mole. Explanation: I was trying to mole the SerialPort class in System.IO.Ports. After adding the mole for System.dll I began to get “no suitable method found to override” errors.  To resolve this issue I simply double clicked the System.moles file to open it in my IDE.  Then I modified the file so that moles were created only for the types under System.IO.  Change System.moles from this: <Moles xmlns="http://schemas.microsoft.com/moles/2010/">  <Assembly Name="System" /></Moles> to this: <Moles xmlns="http://schemas.microsoft.com/moles/2010/">   <Assembly Name="System" />   <StubGeneration>      <Types>         <Clear />         <Add Namespace="System.IO!" />      </Types>   </StubGeneration></Moles>