Sometimes during migrations from VB6 to VS2010 we have found issues when you tried to add an ActiveX control with the VS2010 winforms designer. The issue is only present in VS2010 not on previous versions.
You usually will see an error in the added Interop references, and messages like a missing VBA or StdLib library.
The error has been reported several times so please vote on Connect to make sure MS will consider fixing it.
https://connect.microsoft.com/VisualStudio/feedback/details/557722/errors-utilizing-activex-controls-in-vs-2010
http://connect.microsoft.com/VisualStudio/feedback/details/568769/aximp-error-with-vb6-activex-control
And possible workarounds are running the Aximp manually from the command line and the add the references. You will then need to add the control by hand in your forms. Do not use the designer to add the component, this will try to regenerate the references and reproduice the issue.