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This page is constantly updated with new solutions and troubleshooting hints for problems that can't be solved by me from code.

Troubleshooting installation

Problem: ImportError: No module named BroTools


This error means that Maya can't find BroTools folder under paths that are registered as 'python paths'.

Here are some steps you can do: 1. Make sure you removed BroTools 1.x if you had it installed, it can often cause this error. BroTools 2.x and 1.x are incompatible. You can find instructions on how to remove 1.x on installation page of this documentation. 2. Make sure that you restarted Maya after installation of BroTools 3. Make sure that BroTools folder is called exactly like this BroTools with capital B and T.

If none of it helps, feel free to contact me.

Problem: Maya crashes or freezes when trying to load plugin - either manually through plugin-manager or when using install_step2.mel script.

Solution 1:

Try running this command in Maya as Python:

import PySide2.QtWebEngineWidgets 

If maya freezes or crashes - try disabling your anti-virus and anti-malware software temporarily and run this command again. If it works it means that you're anti-malware or anti-virus software is somehow blocking Maya from starting a Qt web browser window. It is used in BroDynamics for loading and displaying license agreement, welcome window, changelog, about description and other places where text with HTML formatting it required. You may need to adjust your anti-virus or anti-malware software's policies to allow it.

Since version 2.3.0 I've added an option to disable the use of PySide2.QtWebEngineWidgets alltogether and fallback to simple QtTextBrowser. To do this you should open BroTools/config/brotools.cfg file, find the following line:

qtextbrowser_fallback: False

And change it to:

qtextbrowser_fallback: True

This should solve the problem.

This problem was described in this blog post as well:

Solution 2:

Try loading "bullet.mll" plugin through Maya's Plugin manager. If Maya freezes or crashes when trying to load this plugin - it means that you're probably using a GPU or GPU Driver unsupported by Maya. Try updating or reinstalling your GPU driver.

You can still launch BroDynamics by disabling RBD simulation mode. To do this you need to edit \BroTools\config\brodynamics.cfg file, and remove the , "rbd" part from activeModules option. So it will look like this:

activeModules: ["point", "chain_simple", "chain"]

If the problem was with bullet.mll this will allow BroDynamics to load but with RBD tab disabled.

Solution 3:

If you're running 11th gen Intel CPU, Windows 10 and Maya 2019-2020, then this issue might be relevant (even if you dont run those versions still might be worth looking into):

The solution is to add OPENSSL_ia32cap=~0x200000200000000 environment variable as System Variable. You should not need to reboot after that, just restart Maya and try loading BroTools again.

Troubleshooting\Known bugs


RBD Mode crashes maya during tracking or simulation


Try to switch maya parallel evaluation off. To do it, go to Settings - Animation - Evaluation - Evaluation Mode, and set it to DG.


# Warning: WARNING: 2016-11-02 16:34:09.977000:  Tried to run startSimulation, Chain mode, experienced an error: 'module' object has no attribute 'print_' #


You probably selected the chain using Select Hierarchy. Instead you need to simply select all the objects either one by one with CTRL, or you can also Shift-select them, if they are in the same hierarchy. Unfortunately this seems like a bug with Select Hierarchy.


Maya crashing or slowing down while BroDynamics UI is open.


This is expected behaviour, since BroDynamics UI adds a few ScriptJobs, which run when you select something, or when you open a scene. BroDynamics UI uses them to check and update itself accordingly to scene contents and selection. In most cases it should not have any impact on stability or performance, but it may happen. In this case you should just close BroDynamics UI when you don't need it.


Exception of type RuntimeError occured in 'BroTools.common.nodes.init': (kFailure): NULL object returned**


This error was seen in Maya 2016, but it seems like a Maya bug, probably due to early implementation of Parallel Processing (guessing here). For me it vanished on it's own after doing a few random things in Maya (creating another object and trying to run chain, then point simulation).

Problem: Fatal error on undo after using Chain Simulation Mode


This bug seems to happen in Maya 2018.4 and 2018.5 for some people. If this happens and you can't upgrade to Maya 2019 try to remove your prefs folder (make a backup if you'd like to restore it later), and try again.

Problem: Shape Controls of Locators and\or other objects are missing from the Channel Box\Layer Editor tab after loading BroDynamics


This is happens when you load bullet.mll plugin, which is a standard Maya plugin. Bullet physics is used by RBD tab of BroDynamics, and it gets loaded when launching BroDynamics UI.


Unfortunately bullet.mll is a standard Maya plugin developed by Autodesk which I have no control over. The only thing you can do is to disable RBD tab from loading.

To do this go to BroDynamics - Tools - Preferences and remove , "rbd" from the active modules parameter string, so it looks like this:

["point", "chain_simple", "chain"]

Or you can edit config file with a text editor: BroTools\config\brodynamics.cfg

After this restart Maya.