Known Issues

General

1. On some Windows systems, you may encounter an error like the following:

   OSError: [WinError 126] The specified module could not be found. Error loading "C:\path\to\omni.isaac.ml_archive\pip_prebundle\torch\lib\fbgemm.dll" or one of its dependencies.
   

   This issue is caused by missing build tools. To resolve it, install Visual Studio 2022 and then install MSVC v143 - VS 2022 c++ x64/86 build tools through the Visual Studio interface.

2. The replicator Scatter3D OmniGraph node breaks physics when called on a stage using world.

3. If running Omniverse Isaac Sim headless connected via the remote client and you exit on shutdown, the following error can occur, it can be ignored:

   [ext: omni.physx] shutdown
   Fatal Python error: Segmentation fault
   
   Thread 0x00007f46f8faa740 (most recent call first):
   File "..._build/target-deps/kit_sdk_release/_build/linux-x86_64/release/extsPhysics/omni.physx/omni/physx/scripts/extension.py", line 30 in on_shutdown
   File "..._build/target-deps/kit_sdk_release/_build/linux-x86_64/release/plugins/bindings-python/omni/ext/impl/_internal.py", line 225 in shutdown_all
   File "..._build/target-deps/kit_sdk_release/_build/linux-x86_64/release/plugins/bindings-python/omni/ext/impl/_internal.py", line 261 in shutdown_all_extensions
   File "..._build/target-deps/kit_sdk_release/_build/linux-x86_64/release", line 3 in <module>
   

4. When running in a windowed container, the following errors may be ignored and the app continues to run after waiting for awhile:

   ERROR: Could not find a version that satisfies the requirement psutil (from versions: none)
   ERROR: No matching distribution found for psutil
   WARNING: Retrying (Retry(total=4, connect=None, read=None, redirect=None, status=None)) after connection broken by 'NewConnectionError('<pip._vendor.urllib3.connection.VerifiedHTTPSConnection object at 0x7fcdcc284dd8>: Failed to establish a new connection: [Errno -3] Temporary failure in name resolution',)': /simple/psutil/``
   

5. If exiting standalone Python scripts with Ctrl-C, it may need to be done twice to exit.

6. If Nucleus is not working on Docker, see Manually Installing Nucleus in a Container.

7. If more than one asset in URDF contains the same material name, only one material is created. Regardless if the parameters in the material are different. For example, if two meshes have materials with the name “material”, one is blue and the other is red, both meshes will be either red or blue. This also applies for textured materials.

8. MJCF importer does not show the built-in bookmark in the file picker dialog. The bookmark is still available in the content pane and can be copy-pasted into the file picker dialog.

9. If you see a black screen when running on Windows, use the --vulkan command-line argument during startup.

10. Debug Visualizations are not present in fisheye lens cameras that are not pinhole, because that feature is not implemented.

11. Assigning a viewport resolution that exceeds the available VRAM results in the application throwing ERROR_OUT_OF_DEVICE_MEMORY errors. Subsequently, reducing the resolution to a smaller value may lead to a crash.

12. When using World or SimulationContext from omni.isaac.core with OmniGraph, make sure the graphs are created before the World or SimulationContext are initialized.

13. Using replicator’s rep.new_layer() functionality, which creates a new layer in which to place and randomize assets, may lead to issues in simulation scenarios where these assets are used. In such cases the use of rep.new_layer() can be omitted.

14. When running through Python, selecting physics objects and then another object on screen may result in one or more omni.kit.manupulator errors. This error is non-detrimental to the code execution and may be safely ignored.

15. Dragging and dropping an asset with default values in OmniGraph nodes should be saved with scene and reloaded before hitting Play to make sure all values are correctly set.

16. Error on exiting ./isaac-sim.headless.native.sh from UI.

    [Error] [carb.livestream.plugin] nvstPushStreamData timeout for eye 0, stream (nil).
    

17. Quadruped Robot is not able to move backward with NUM 2 or Down Arrow keys.

18. Cortex samples with ROS synchronization may perform abnormally and not be able to execute the task if the running FPS drops below 25 FPS.

19. If randomized materials are not loaded on time for synthetic data generation the rt_subframes must be set to be at least 2.

20. Some grippers with parallel mechanism (that is, Robotiq 2F-85 and 2F-C2) have links that do not move with rest of the gripper.

21. Multiple Robot ROS2 Navigation tutorial has high CPU usage. If you observe instances of robots colliding or experiencing localization issues, it’s likely because the Nav2 stack is unable to properly synchronize with sensor data, resulting in missed controller commands.

22. There can be many warnings and other messages when running Isaac Sim. The amount of log output can be reduced by using the following command line arguments:

    --/log/level=error --/log/fileLogLevel=error --/log/outputStreamLevel=error
    

23. Using Replicator to write to S3 buckets with the built-in backend in Windows may require setting the credentials in the environment variables instead of the AWS config files. This is because of a possible path parsing error in boto3 on Windows.

24. XR extensions do not work properly on Windows.

25. When running standalone examples in Windows, in some scenarios, threads may not be properly cleaned up when the application is closed. This can usually be ignored because the application will still succesfully close. As a workaround, you can add multiple standalone_app.update() calls before calling standalone_app.close().

    Windows fatal exception: access violation
    
    Thread 0x00000634 (most recent call first):
    

26. The ROS2 QoS Profile OmniGraph node is unable to save custom profiles unless you manually change the createProfile input to “Custom” first before updating the other fields.

27. On some multi GPU systems when creating a render product the main viewport will go black, the render product will continue to work correctly

Warnings

1. Warnings similar to the following can be ignored:

   • [Warning] [omni.usd] Warning (secondary thread)

   • [Warning] [carb.tasking.plugin] Counter 0x7f25e002f8d0

   • [Warning] [rtx.neuraylib.plugin] [MDLC:COMPILER]   1.0   MDLC   comp warn

   • [Warning] [rtx.mdltranslator.plugin] Unable to resolve

   • [Warning] [omni.tagging.plugin] Failed to discover tagging service

   • [Warning] [omni.isaac.dynamic_control.plugin] DcFindArticulationDof: Function called while not simulating

   • [Warning] [omni.isaac.dynamic_control.plugin] DcSetDofProperties: Function called while not simulating

   • [Warning] [omni.client.plugin]  Tick: authentication: Could not connect to discovery service at "wss://...

2. If Physics is not needed this message can be ignored:

   • [Warning] [omni.physx.plugin] Physics USD: Physics scene not found. A temporary default PhysicsScene prim was added automatically!

3. If there is unwanted noise in simulated depth images, disable anti-aliasing under the Render Settings > Ray Tracing > Anti-Aliasing tab by setting the Algorithm to None.

4. Pyperclip is used to copy text in some extensions, if you see the following message refer to the link to install a supported copy/paste mechanism:

   Pyperclip could not find a copy/paste mechanism for your system.
   For more information, please visit https://pyperclip.readthedocs.io/en/latest/index.html#not-implemented-error
   

5. If the parent prim of a joint does not correspond to body 0 then the value returned from physX will be the negation of the USD value.

6. If you see the following UI warning, followed by a call stack, it can be ignored:

   • [Warning] [omni.ui] Container::addChild attempting to add a child during a draw callback

7. If you see warnings similar to the following when running ROS 2 sample assets, they can be ignored:

   [Warning] [omni.graph.core.plugin] /iw_hub/front_hawk/left_camera_publish_camera_info: [/iw_hub/front_hawk] OmniGraph Warning: OgnROS2CameraHelper:sensor_type == camera_info is deprecated as of Isaac Sim 4.1.0 in favor of OgnROS2CameraInfoHelper.
              (from compute() at line 208 in /home/horde/workspaces/omni_isaac_sim/_build/linux-x86_64/release/exts/omni.isaac.ros2_bridge/omni/isaac/ros2_bridge/ogn/python/nodes/OgnROS2CameraHelper.py)
   

8. If you see warnings similar to the following, they can be ignored:

   [Warning] [omni.client.python] Detected a blocking function. This will cause hitches or hangs in the UI. Please switch to the async version
   

   Make sure you have access to the Internet or a Nucleus server.

Errors

1. Errors similar to the following can be ignored when running headless:

   [Error] [carb.windowing-glfw.plugin] GLFW initialization failed.
   

   [Error] [carb] Failed to startup plugin carb.windowing-glfw.plugin (interfaces: [carb::windowing::IGLContext v1.0],[carb::windowing::IWindowing v1.2]) (impl: carb.windowing-glfw.plugin)
   

   [Error] [carb.scripting-python.plugin] RuntimeError: Failed to acquire interface: carb::windowing::IWindowing (pluginName: nullptr)
   
   At:
   /isaac-sim/kit/exts/omni.kit.window.cursor/omni/kit/window/cursor/cursor.py(27): on_startup
   /isaac-sim/kit/plugins/bindings-python/omni/ext/impl/_internal.py(141): _startup_ext
   /isaac-sim/kit/plugins/bindings-python/omni/ext/impl/_internal.py(174): startup_all_extensions_in_module
   /isaac-sim/kit/plugins/bindings-python/omni/ext/impl/_internal.py(225): startup_all_extensions_in_module
   PythonExtension.cpp::startup()(2): <module>
   
   [Error] [omni.ext.plugin] [ext: omni.kit.window.cursor-1.0.1] Failed to process python module extension in '/isaac-sim/kit/exts/omni.kit.window.cursor/.'.
   

2. These errors can be ignored while running the running Kit Remote Client, if the client works as normal:

   ERROR [BifrostClient: Streamer] {2B436200} -  updateVideoSettingsForNVbProfile: profile 8 is not handled
   ERROR [NVST:ClientSession] {1E8D2700} -  Number of channels(2) is not valid for surround configuration
   ERROR [NVST:ClientSession] {1E8D2700} -  Either in stereo or error in receiving opus information from server
   
   ERROR [LAVCDecoder] {FC4A0700} - GERONIMO_ERROR 0xC0040006 GERONIMO_LAVCDECODER_DECODE: Packet decode failure.
   ERROR [GIOInterface] {DAFFD700} - GERONIMO_ERROR 0xC0020003 GERONIMO_IOINTERFACE_INVALID_AUDIO_FUNC: Audio Renderer is NULL.
   ERROR [NVST:ClientLibraryWrapper] {1E8D2700} -  Cannot find streamEventRaised for stream.media type 1
   ERROR [NVST:ClientLibraryWrapper] {1E8D2700} -  Cannot find streamEventRaised for stream.media type 2
   
   ERROR [NVST:RtspSessionPocoBase] {FB280700} -  perform() failed: 0
   ERROR [NVST:RtspPocoEvent] {FB280700} -  RTSP-XNvEvent Polling failed: 0, rc: 408
   
   ERROR [NVST:UdpRtpSource] {F9A7D700} -  UDP RTP Source: failed to receive data (Error: 0x80000013)
   ERROR [NVST:RtpSourceQueue] {F9A7D700} -  RtpSourceQueue: failed to read RTP packet (Result: 0X80000013)
   ERROR [BifrostClient: NvscWrapper] {1D0CF700} - Received old frame - current 7536 received 0
   ERROR [BifrostClient: Interface] {2B436200} - nvbSendInputEvent(). SessionIdentifier is ''
   

3. Error similar to the following happens when STOPPING and STARTING simualtion again when using Isaac core world class. To stop the error trail, Reset the scene with one of the world.reset methods (in the core samples, this happen when pressing the RESET button on the UI).

   2021-06-01 19:16:51 [65,842ms] [Error] [omni.kit.app._impl] [py stderr]: AttributeError: 'NoneType' object has no attribute '<...>'
   
   At:
   <...>
   

4. If an asset contains an Action Graph and the Action Graph window is closed before re-opening the same asset, the following errors may appear and can be ignored:

   [Error] [omni.usd] TF_PYTHON_EXCEPTION (secondary thread): in TfPyConvertPythonExceptionToTfErrors at line 114 of /buildAgent/work/ca6c508eae419cf8/USD/pxr/base/tf/pyError.cpp -- Tf Python Exception
   
   [Error] [omni.kit.app.impl] [py stderr]: sys:1: RuntimeWarning: coroutine 'OmniGraphModel.__delayed_prim_changed' was never awaited
   RuntimeWarning: Enable tracemalloc to get the object allocation traceback
   
   [Error] [omni.graph] Invalid GraphObj object in Py_Graph in getNode
   

5. Errors when converting ShapeNet models may appear from the omni.kit.asset_converter extension when textures for the target model are missing from the input dataset. These errors can be ignored.

   [Error] [omni.kit.asset_converter.impl.omni_client_wrapper] Cannot copy from */images/texture2.jpg to */textures/texture2.jpg, error code: Result.ERROR_NOT_FOUND.
   

6. Errors when livestreaming. These errors can be ignored.

   [Error] [carb.livestream.plugin] nvstPushStreamData timeout for eye 0, stream (nil).
   

7. Errors when using a Jupyter notebook. These errors can be ignored.

   [Error] [omni.kit.app.plugin] Can`t delay app ready event, it was already sent. Requester name: omni.usd
   

8. Errors while generating samples with flying_things_4d.yaml for larger value of --num-scenes (specially when running for stress test):

   [Error] [omni.physicsschema.plugin] Rigid Body of (/Replicator/SampledAssets/Population_9658d6d1/Ref_Xform_05/Ref) missing xformstack reset when child of rigid body (/Replicator/SampledAssets/Population_9658d6d1/Ref_Xform_05) in hierarchy. Simulation of multiple RigidBodyAPIs in a hierarchy will cause unpredicted results. Please fix the hierarchy or use XformStack reset.
   

9. Error like this when running Composer can be ignored.

   [Error] [omni.graph.core.plugin] /Replicator/SDGPipeline/OgnSampleCombine_03: [/Replicator/SDGPipeline] Assertion raised in compute - AttributeData 'OgnSampleCombine_03.outputs:samples' of type 'float3[]' required array of elements of length 3, got array with elements of size 1
   

10. When using the surface gripper between two objects that contain articulation root, the following error may appear and the surface Gripper won’t work. To avoid it, disable the Articulation API from the picked object.

    [Error] [omni.physx.plugin] PhysX error: PxD6JointCreate: actors must be different
    

11. Error regarding omni.sensors plugin when starting Isaac Sim on Windows. This error can be ignored.

    [Error] [carb] [Plugin: omni.sensors.nv.lidar.ext.plugin] Dependency: [omni::sensors::lidar::IGenericModelOutputIOFactory v0.1] failed to be resolved.
    

12. Fatal error regarding omni.sensors plugin when running RTX Radar. Unless you have manually disabled Vulkan and MotionBVH, this error appears if you are using a below-minimum-spec GPU. Your GPU must be Ampere architecture or newer.

    [Warning] [omni.sensors.nv.radar.wpm_dmatapprox.plugin] MotionBVH activation state 0 doesn\'t match requested state 1
    [Fatal] [omni.sensors.nv.radar.wpm_dmatapprox.plugin] Running radar without MotionBVH is disallowed, to force it use --/app/sensors/nv/radar/runWithoutMBVH=true
    If you are running on Windows and have motionBVH enabled, be sure to enable Vulkan as well by passing --vulkan
    

13. Error regarding failure to process writer attach request when playing scene containing an OmniGraph, after changing timeCodesPerSecond setting. To resolve, save the scene, reopen it, then play it again.

    [Error] [omni.graph] Invalid Node object passed to Graph.get_graph_from_node
    [Error] [omni.isaac.core_nodes.impl.base_writer_node] Could not process writer attach request (<omni.replicator.core.scripts.writers.NodeWriter object at 0x7355b3d175b0>, None), Invalid NodeObj object in Py_Node in getAttributes
    

14. In omni.replicator.object, the description file demo_shader_attributes_diffuse.yaml can have a corrupted JPEG error that the picture is not written before it’s used. We are looking into fixing it.

    [Error] [gpu.foundation.plugin] Couldn\'t process /tmp/carb.F3srY8/randomized_output.jpg, it might not have written completely. Reason: Failed to load image: Corrupt JPEG
    

15. omni.usd LoadModule errors can be ignored.

    [Error] [omni.usd] USD_MDL: in LoadModule ...
    

Hang

1. On windows, when using the extension manager, clicking on the dependencies window will cause the viewport to go black and hang.

2. The WebRTC Client on Firefox may appear to hang after a few seconds when clicking the Play button. Using the Google Chrome or Chromium browser is recommended.

3. Isaac Sim may hang if a browser pop-up for logging into Nucleus is closed before completing the login. Force restart of Isaac Sim is required.

4. Isaac Sim may hang if it is shutdown from the File > Exit Fast (Experimental) menu when using livestreaming. Force close Isaac Sim and the livestream client when this happens.

5. The Omniverse Streaming Client may hang after Isaac Sim exits with the File > Exit menu. Force close the Omniverse Streaming Client when this happens.

Crash

1. Using RTX Lidar and a physics scene with GPU Dynamics enabled can lead to a crash in some cases. Disable GPU dynamics in the physics scene and set the broadphase type to MBP if you encounter this issue.

2. Docking windows in the isaac-sim UI when an RTX Lidars simulation is running will likely lead to a crash. Pause the simulation before re-docking the window.

3. Shutting down the physics.tensors extension before the Python garbage collector cleans up the related objects can lead to a crash. To prevent this, manually set the related tensor API objects in Python to None before unloading the extension.