Mental Ray is Missing in Maya 2016 – Can’t find Mental Ray
Mental Ray Plugin Needs to be downloaded from Autodesk separately. It is not included in the download.
1. Download it here. http://knowledge.autodesk.com/support/maya/downloads/caas/downloads/content/mental-ray-plugin-for-maya-2016.html
2. Close Maya and Reopen Maya
3. Window – Settings/Preferences – Plug-in Manager
4. Scroll to the bottom of the Plug-in Manager
5. Find Mayatomr.mll and Place a check in Loaded and Auto Load
6. Click the X in the upper right to close. No need to save.
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When you start Maya, may not see Mental Ray. You will need to turn the plug-in on. Here is how to do it.
1. Window – Settings/Preferences – Plug-in Manager.
2. Scroll to the bottom of the list.
3. Check the boxes next to Mayatomr.mll
You can see it is loaded by to the Render Settings. Click on the Movie Icon below or go to Window – Rendering Editors – Render Settings to open the Render Settings.
Click the dropdown arrow and select mental ray – If it is not there, then you must go back to the plug-in manager and make sure the box is checked.