Uninstall the previous version of SItoA from the File->Add-on->Uninstall menu option in Softimage:
After the uninstall process is completed, and before installing the new version, make sure there is no SItoA folder in the Add-ons location. If a user is running SItoA while another user is uninstalling it, the Add-on may not be completely removed from the workgroup, leaving things in a corrupted state.
There is also an Arnold Renderer Custom preferences preset file stored in the folder;
which is not deleted by uninstalling the addon. Make sure you delete the Arnold Render.Preset file here. Also, the changes done in the Custom preferences are stored in the default.xsipref from the same folder. Open it in a text editor and make sure there are no Arnold entries (if there are, delete those lines).
Finally, you can install the new SItoA version (see the Installing SItoA section).
If loading existing scenes, be sure to run the SITOA_RegenerateRenderOptions() command from the script editor, or from the Arnold top menu after opening a scene. This will ensure the update of the PPGs, adding new parameters or removal of old parameters etc. in a scene created with a previous version of SItoA (also see the SItoA Commands section).
- Uninstall the old SItoA (File->Add-on->Uninstall).
- Check there is no SItoA folder in the Add-ons location.
- Install the new SItoA (File->Add-on->Install).
- Run SITOA_RegenerateRenderOptions()