COM object in C# VS2008: Error loading type library/DLL

I am trying to reference a third party COM DLL from a Visual Studio 2008 project (.NET 3.5 SP1) on Vista Ultimate.

I ran the setup for the COM component, and then discovered that it was not the right setup. So I uninstalled and ran the correct install. After adding the reference to a new C# project, not all the object methods are available that should be.

One of the compiler errors is:

Could not determine the dependencies of the COM reference "APIV2_COMLib". Error loading type library/DLL. (Exception from HRESULT: 0x80029C4A (TYPE_E_CANTLOADLIBRARY))

Thnking the registry might've retained incorrect values, I uninstalled the component and searched the registry for any sign of detritus, but found none. Still, reinstalling gives the same error.

Searching online reveals that others have experienced the same problem 'Odd COM error when upgrading to 3.5' in MSDN forums but I haven't found answers.

My colleagues use the same COM object from .NET code (though not higher than .NET 2.0 or on Vista).

Sounds to me like there's still something lingering in the registry that you weren't able to cleanse. Try mucking around on a virtual machine as a "fresh install" to see if it's truly the case. (Unless you're already sure this is exactly the problem...)