Hello,
The error code -2130313112, or
APIERR_BADPARS means that you have given invalid or inconsistent parameters to an API function, and as such, the operation didn't succeed. I recommend looking into the API
documentation of the function, which produces the error.
As for the
ACAPI_Attribute_ModifyExt function, the most common causes of this error code is passing null pointers for required arguments.
You can find a comprehensive list of error codes and their meanings on the
ARCHICAD API site.
Also, in the future, please refrain from reviving 8-year-old threads in the forum. You can always create a new thread, and ask for information there.
Best regards,
Dénes