Hi @pim , thanks for reaching out us.
Although you've already set this thread as SOLVED can you, for the sake of a better knowledge-sharing, describe better what you mean by "I tried to update a R20 C++ plugin."? What steps did you actually run through? What version of VisualStudio are you using? What version of ProjectTool did you used?
Finally, please make sure you use our tagging system to enhance topic search.