By default, the Visual Basic .NET compiler does not enforce strict data typing and uses late binding to access methods, properties and fields of the classes. This is somehow simplifies the coding for certain kind of people but it has several implications:

That's why a very good advice for Visual Basic .NET programmers is to use Option Strict On for their programs. Unfortunately, it is not always possible due to legacy code or personal long-term preferences that are hard to change.

Eazfuscator.NET provides a special compatibility mode that allows to workaround the issues with late binding. It comes at the expense of a lower obfuscation coverage but your code remains functional and runs perfectly after obfuscation.