Pre-Req for VrayVRMatMTL network rendering?

[SnipeyX]

Any ideas why the VrayVRMatMtl isn't working on backburner network rendering when it works locally? It shouldn't be the usual 'do your nodes have access' network issue as I'm loading the vrmat files from the same file server we always use. Is Python required to be installed on machines to use the VrayVRMatMtl? I remoted in to one of the rendernodes and actually opened Max, when I create a VratVRMatMTL and load the same .vrmat file, there are no materials listed to choose from. If I press open editor I get a "failed to initialize Python editor" dialog.

Max Design 2015 Ext2

[svetlozar.draganov]

Does the same error message appears if you create a new VrayVRmatMtl and click Open Editor without loading any pre-made materials?
Does the issue appears only with BackBurner or it persists with V-Ray DR as well?
Would it be possible to send us the log files from the machines which do no render VrayVRmatMtl materials correctly?

[SnipeyX]

Upon further testing it looks like this only works on machines that have Python installed. Period. I just happened to have Python installed on my desktop, but we've tried all of our farm machines and some other regular desktop machines and mine is the only one that doesn't get that error. Upgraded all machines to 3.10.03 - still persists.

Started from a blank scene, created a new VrayVRMatMTL without loading a file, same error message - "Failed to initialize Python editor".
Farm machines are 14 machines, all running Win7, specs vary 16/32core. Doesn't work via Backburner, DR, or opening Max locally. In all cases the VRMat objects seem to become unrenderable - they don't even show in alpha. VrayLog doesnt show anything weird at verbosity 4, it claims it's loading the materials and object names, proper number of render instances, creates a render mesh, etc. Just nothing shows in the buckets. If I load a scene saved from my machine on those, same results, save it and load on mine, renders on mine fine.

[svetlozar.draganov]

It seems that V-Ray cannot access the Python which comes with 3DSMax installation for some reason.
What user account type did you use when installing V-Ray? Can you try to reinstall it using Administrative account?
Does the Python folder exists in 3DSMax Design root directory:

[svetlozar.draganov]

Would you please send us the "vmax_stderr.txt" file from some of the machines which do not render properly VRayVRmat-materials?
The file should be located under the following folder:
C:\Users\YOUR_USERNAME\

[SnipeyX]

The python folder does exist in root.

The vmax_stderr.txt file exists but is empty. There is a vmax_stdout.txt which contains this: "

About to make our qapp
after make qapp
C:\Program Files\Autodesk\3ds Max Design 2015\python/Lib/site-packages\VRayPlugins.xml
Made it after UIManager.initialize
registering hook
starting hook

The install was done via a commandline with an xml install config, and that appears to be the issue. I re-ran the install manually via the UI and now it works.

vray_adv_31003_max2015_x64.exe -gui=0 -configFile="vray2015installConfig.xml" -quiet=1
This is the xml file I'm using to install, is there something different I need to do?
<DefValues>
<Value Name="MAXROOT" DataType="value">C:\Program Files\Autodesk\3ds Max Design 2015</Value>
<Value Name="PLUGINS" DataType="value">$MAXROOT\plugins</Value>
<Value Name="OPEN_README" DataType="value">0</Value>
<Value Name="OPEN_CHANGELOG" DataType="value">0</Value>
<Value Name="INSTALL_WIBU" DataType="value">0</Value>
<Value Name="REG_LIC_SERVER" DataType="value">0</Value>
<Value Name="INSTALL_TYPE" DataType="value">0</Value>
<Value Name="REMOTE_LICENSE" DataType="value">1</Value>
<Value Name="VISIT_SPOT3D" DataType="value">0</Value>
<Value Name="SHOULDUNINSTALL" DataType="value">0</Value>
</DefValues>

[svetlozar.draganov]

Glad to hear that it works fine with UI installation but it is very strange why the python folder is missing from 3DSMax root directory.
Would it be possible to reinstall 3DSMax and let us know if the folder is there afterwards?

[SnipeyX]

No no, the python folder DOES exist, it is not missing.

[svetlozar.draganov]

Thanks for the clarification.
Let me check if the same issue appears here if V-Ray is Silent Installed.

[svetlozar.draganov]

We've just run a Silent Installation with the same XML file but we couldn't reproduce the issue.
Have you ever installed V-Ray via UI on the machines which you have issues?

Would it be possible to uninstall V-Ray on the machine you've installed it via UI, then run the same command-line installation and test if the same issue appears again?

[SnipeyX]

Likely only ever ran install via command line on these (until earlier troubleshooting). So I just uninstalled on one of the machines that had been working. Re-installed via the command line, and now I get the error again. Max Design 2015. These did have vray 2 installed on them, as well as for Max Design 2014. When I uninstalled Vray 3 today, I uninstalled it for both 2014 and 2015, so there should be no more vray on the machines until I just ran the silent installer. Windows 7 Enterprise SP1.

The account running everything (both at install & when i run Backburner / Max) does appear to be a "service account". It is in the Administrators group, but perhaps this 'service account' status changes somehow something the installer is supposed to be doing with python when it installs via the cmd file?

[svetlozar.draganov]

Not sure if this is related to the Windows User Account or something into the installer is broken.
Let's try one more installation, please follow the steps bellow:

0.Un-install V-Ray 3.x if it is already installed.
1.Open CMD.EXE as Administrator(Right Click > Run As Administrator)
2.run V-Ray installer via the following command:
C:\path\to\vray\installer\vray_adv_31003_max2015_x 64.exe -gui=0

3.Follow the installer steps and complete the installation.
4.Notice that a "config.xml" file will be automatically created into the same directory once the installation is completed.
This file will store all the options you've chosen during the installation and it could be used for a Silent Installation afterwards.

5.Open 3DSMax and check if the same issue appears again.