FIX: Type Library Importer (Tlbimp.exe) Fails to Parse Certain Type Libraries

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Article ID: 316552 - View products that this article applies to.
This article was previously published under Q316552
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If you use two coclasses, such as Test and TestClass, and a method or property that is named TestClass, the Type Library Importer (Tlbimp.exe) fails, and you receive the following error message:
TlbImp error: System.TypeLoadException - Type Test.TestClass from assembly TestClass tried to override method TestClass but does not implement or inherit that method.


To resolve this problem, obtain the latest service pack for Microsoft .NET Framework. For additional information, click the following article number to view the article in the Microsoft Knowledge Base:
318836 INFO: How to Obtain the Latest .NET Framework Service Pack


This bug was corrected in .NET Framework (2003|1.1).


Steps to Reproduce the Behavior

  1. Create a new .idl file with the following code, and then save the file as Test.idl.
    [uuid(B109B266-FFA6-482a-BF17-8A1F49A83E6E), version(1.0), helpstring("Q316552 1.0 Type Library")]
    library Test
    	[uuid(3CD087A6-3693-4c97-A599-EC7C231C59CA), oleautomation]
    	interface ITest : IUnknown 
    		HRESULT TestClass([in] int i);
    	[uuid(08045E96-5742-486c-8604-925BBEB9AD61), helpstring("Test Class")]
    	coclass Test 
    		[default] interface ITest;
    	[uuid(13803111-45FA-4368-A540-66030894AE7F), helpstring("TestClass Class")]
    	coclass TestClass 
    		[default] interface IUnknown;
  2. Run Microsoft Interface Definition Language (MIDL) against Test.idl to generate the corresponding type library file, as follows:
    midl test.idl
  3. Run Tlbimp to import this type library, as follows:
    tlbimp test.tlb /out:TestNET.dll /namespace:Test
    Note that Tlbimp fails with the System.TypeLoadException error message.


Article ID: 316552 - Last Review: October 24, 2013 - Revision: 3.1
  • Microsoft .NET Framework Software Development Kit 1.0 Service Pack 2
  • Microsoft .NET Framework Software Development Kit 1.0 Service Pack 2
  • Microsoft .NET Framework Class Libraries 1.0
kbnosurvey kbarchive kbbug kbcominterop kbfix KB316552

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