This post is in refrence to running Standalone converter from a server seperate of P2V source and target.
Error: The method 'ConverterValidateTargetStorageParams' does not exist on the object
Fix: Uninstall Converter Agent, retry P2V.
Today I was attempting to P2V a running Windows server and revieve this error on the "Data to Copy" section in the "view/edit settings" portion of the converter setup wizard. I recalled that when I tested the P2V process (successfully) with this Windows machine that I was using Converter version 4.0.0 and that I chose options to manually uninstall the converter agent. This time, howeve, I was using the upgraded Converter version 4.0.1 and was receiveing this mysterious error that I found no mention of on Google searches or the VMWare site. Luckily it seems the error was cleared by removing the Converter Agent and letting the Converter App install the shiney new version.
I hope this is helpful.