Compiler Error CS0433

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The type TypeName1 exists in both TypeName2 and TypeName3

Two different assemblies referenced in your application contain the same namespace and type, which produces ambiguity.

To resolve this error, use the alias feature of the /reference (Import Metadata) (C# Compiler Options) compiler option or do not reference one of your assemblies.

Example

This code creates the DLL with the first copy of the ambiguous type.

// CS0433_1.cs
// compile with: /target:library
namespace TypeBindConflicts 
{
   public class AggPubImpAggPubImp {}
}

This code creates the DLL with the second copy of the ambiguous type.

// CS0433_2.cs
// compile with: /target:library
namespace TypeBindConflicts 
{
   public class AggPubImpAggPubImp {}
}

The following example generates CS0433.

// CS0433_3.cs
// compile with: /reference:cs0433_1.dll /reference:cs0433_2.dll
using TypeBindConflicts;
public class Test 
{
   public static void Main() 
   {
      AggPubImpAggPubImp n6 = new AggPubImpAggPubImp();   // CS0433
   }
}

The following example shows how you can use the alias feature of the /reference compiler option to resolve this CS0433 error.

// CS0433_4.cs
// compile with: /reference:cs0433_1.dll /reference:TypeBindConflicts=cs0433_2.dll
using TypeBindConflicts;
public class Test 
{
   public static void Main() 
   {
      AggPubImpAggPubImp n6 = new AggPubImpAggPubImp();
   }
}