If you have a VBA macro in Microsoft Excel and a webreference to a webservice, you might get the famous Compile error: Can’t find project or library SoapClient30.
In mine case it wasn’t missing the C:\Program Files (x86)\Common Files\microsoft shared\OFFICE12\MSSOAP30.DLL but an old reference to the Office 11 components library.
> Open the Microsoft visual basic editor
> Tools > References…
> Remove all dll’s with "MISSING" for it, if you don’t have any start with deleting de selected dll until a dll appears witch is missing.