Error with existing COM Reference or adding a new one

Question

Let me preface this by saying that I am unfamiliar with COM references, and I am using VS2010 on a Windows 7 64 bit machine. This morning I pulled down an existing project from TFS. I then tried to build the project and received this error:

The type or namespace name 'validatecom' could not be found (are you missing a using directive or an assembly reference?)

And I get this warning:

Cannot get the file path for type library "d0b51ccc-aa31-47a1-b3ff-b8ed71c522a1" version 1.0. Library not registered. (Exception from HRESULT: 0x8002801D (TYPE_E_LIBNOTREGISTERED))

When I check the references, sure enough, I see the yellow exclamation in the only COM Reference in the solution. After some fruitless testing, I decided to try adding a new COM Reference.

Add Reference -> COM tab -> random M$ library

This results in a new reference with a yellow exclamation. I try building the project to see if I get the same error. This time I receive this error:

Encountered multiple versions of the assembly with GUID '23d736f1-acbc-11d3-b0e8-00104bff2710'. Try pre-importing one of these assemblies.

And I get this warning:

Cannot find wrapper assembly for type library "ADODB".

I have no idea if these two errors are related. If not, then resolving the first certainly takes precedence over the last.

Answer 1

One other thing to check for is if your COM library is registered in Windows' registery, which can you done like this:

%windir%\system32\regsvr32 YourComLibrary.dll

Next you'll need to create an interop .NET DLL that wraps around the COM library you are trying to reference in your C# project. The way to do this is by running the type library importer utility (use the Visual Studio 2010 command prompt):

tlbimp.exe YourComLibrary.dll /out:YourWrappedComLibrary.dll

As for the ADODB reference, you'll likely need to reference the Primary Interop Assembly for ADO (ADODB). This can be found on your machine at the following location. Add a reference to this and you should be good.

C:\Program Files (x86)\Microsoft.NET\Primary Interop Assemblies\adodb.dll

Hopefully the above gets you going. Its been too long since I've messed with COM... memory maybe foggy a bit. Enjoy!