Arnold Compatibility 

This is a list of the MtoA versions that Ornatrix Arnold translator was built against and are supposed to properly render Ornatrix hair:

Maya Version MtoA Version supported by Ornatrix
2016, 2016.5 3.1
2017 3.3
2018 4.2
2019 5.1
2020 5.2
2022-2024 5.3

The first and second MtoA version number must match the one Ornatrix was built against, otherwise the translator won't work. The remaining numbers may be different.
For example, in Maya 2019 Ornatrix will work with any MtoA 5.1.x version, but won't work with any of the 5.0.x or 5.2.x versions.

Ornatrix tries to support the latest published version of MtoA (Maya to Arnold translator). This may be newer than the version that comes with Maya, so you may need to install the latest one from the Arnold website.
Whenever you upgrade to the latest Ornatrix version and you find that hair no longer renders in Arnold, check for a newer MtoA version at https://arnoldrenderer.com/download/

It is possible to check which version of MtoA is Ornatrix linked to by inspecting the contents of the plug-ins\extensions directory under the Ornatrix installation root (usually C:\Program Files\Ephere\OrnatrixMaya20xx). If there is a file named for example OrnatrixTranslator52.dll then the required MtoA version is 5.2.

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