I got this from another site:
REALbasic and Visual Basic use the BASIC language and have 'basic' in their name but, in reality, have very little in common. Things such as file I/O and database access are wildly different between the two. It takes a skilled developer to accurately convert from Visual Basic to REALbasic. Don't be fooled by free and inexpensive 'converter' applications-they don't work!

Converting from VB6 to REALbasic should be a no-brainer, right? Wrong. While they both have basic in the name, they really are completely separate languages, each with their own set of peculiarities. Yes, there are many similarities between the languages but that doesn’t mean it’s easy.

REAL Software has had the Visual Basic Project Converter (VBPC) for a while and was last updated in early 2005. It’s free for download. I would recommend that you don’t even bother – you’re better off converting by hand.
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