Christophe Weisse


Thanks for reaching out, to have a swift feeback could you open a ticket in the Zemax support system ? Please navigate to, or send an e-mail to

I can share here some 1st level troubleshooting. Can you please:

  • make sure you copied the exe under {Zemax}\ZOS-API\Operands. If it is not in the right folder (and so if OpticStudio can’t find it), you will get a ShellExcute Error.
  • try to recompile the UDOC EXE with the latest DLLs (ZOSAPI.dll, ZOSAPI_Interfaces.dll, and ZOSAPI_NetHelper.dll). There are some changes in the API from version to version, and this might fix the issue you are seeing. To make sure you have the latest versions of these DLLs, you can find them in C:\Program Files\Ansys Zemax OpticStudio 2023 R1.03.


All the best,