Issue:
When opening a scene containing
Nvidia Mental Ray elements in 3ds Max, the message "Missing Dlls" appears and provides a list of Mental Ray class DLLs that are missing.
Note: The Mental Ray files listed may vary depending on the scene or installation. The following example shows some of the missing Mental Ray components that may appear:
FileName: mrmaterialattribs.gup Class: mental ray: material custom attribute
FileName: mrMaterialAttribs.gup Class: mental ray: Indirect Illumination custom attribute
FileName: mrMaterialAttribs.gup Class: mental ray: light shader custom attribute
Causes:
These DLL warnings are related to the Nvidia Mental Ray render engine (now discontinued) and some (or all) of the plug-in components being missing when loading a scene.
For example:
- 3ds Max is missing core installation components for the NVIDIA Mental Ray plugin.
- The scene file being opened was made using legacy NVIDIA Mental Ray components without Mental Ray being installed for that software version.
Solution:
To remove the warnings, try the following solutions based on the current 3ds Max setup:
If using 3ds Max 2020-2021
Go to the Rendering > Scene Converter menu and do one or more of the following:
- Check the function Open Scene Converter on File Open when Missing Legacy Plugins and Automatically Remove Missing Legacy Assets on File Open. To remove the assets without a warning, uncheck the first option but leave the second option checked. Note: Be aware that "missing dll's" warnings will still be displayed if other legacy nodes than Mental Ray nodes are in the scene file.
- To suppress the warnings entirely, see How to suppress pop-up windows, dialogs, or warning messages when opening a scene in 3ds Max.
- Alternatively, chose RemoveInvalidLegacyElements from the drop down at Current Preset and convert the scene. Enable Open Scene converter on file open... and Automatically remove missing legacy asstets on File Open:
To fix Mental Ray materials appearing as black or missing attributes in 3ds Max 2021
If running 3ds Max 2021 on a system with 3ds Max 2020 also installed, pointing 3ds Max 2021 to the 3ds Max 2020 plugin\Nvidia folder still allows legacy Mental Ray materials to be recognized (and converted) by the Scene Converter, and they will not appear black upon import.
- Go to "C:\Users\<username>\AppData\Local\Autodesk\3dsMax\ 2021 - 64bit\ENU
- Find the Plugin.User.Settings .ini file. Open it in a text editor, and add a second line under "Directories" so that it looks like the following:
[Directories]
Additional MAX plug-ins=C:\Program Files\Autodesk\3ds Max 2021\PlugIns\
Additional MAX plug-ins NVIDIA=C:\Program Files\Autodesk\3ds Max 2020\PlugIns\NVIDIA\Plugins\
[Help]
(To make this process easier, cut and paste the second line from the example above into the 3ds Max 2021 Plugins.User.Setting.ini file.)
- Re-save the .INI file and restart 3ds Max 2021. You should then be able to reload your mental ray scenes and convert the materials.
If Mental Ray is missing or not installed (3ds Max 2017 and earlier)
If Mental Ray is missing or not installed in the 3ds Max Render Setup window, the render engine needs to be installed again.
- Install Mental Ray from the 3ds Max installer package using the Setup.exe file. The default file location is:
C:\Autodesk\Autodesk_3ds_Max_2017_EFGJKPS_Win_64bit_wi_en-US
If installing or re-installing Mental Ray for 3ds Max 2018
Although Nvidia discontinued Mental Ray in November 2017, installation files for the 2018 version (for 3ds Max and Maya) can still be downloaded at this archival link.
If Mental Ray encounters errors after installation
See this blog post for information on how to fix this.
If opening a legacy Mental Ray scene file in 3ds Max 2018 or newer
Scenes that contain legacy Mental Ray items, such as materials and lights require that these items be updated to supported render components for newer versions of 3ds Max. Should legacy Mental Ray components be used within older scene files and need to be removed:
- Update lights and other Material Editor components manually or by using the Scene Converter.
- Note: The Scene Converter can be used to specify materials and lights that need to be converted from Mental Ray to a format 3ds Max 2019 and newer can recognize (such as the ART or Arnold render engines).
For more information on the changes in Mental Ray rendering, see:
Changes to NVIDIA Mental Ray rendering for 3ds Max 2018 and more recent versions.
Note: Although the Mental Ray renderer was available previously for 3ds Max 2018 from the Nvidia Rendering Forums, it is no longer available and those forums have been closed.
If opening a scene file where no Mental Ray components are being used
If Mental Ray is not being used within any scene files, and is not installed on the machine but receiving a DLL warning,
perform a Clean Uninstall of 3ds Max to remove the errors.
Products:
3ds Max;
