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Known Issues


64-core Machines

The Zync 64-core machine type is currently in alpha and thus can still be unstable for some workloads. In particular certain Vray scenes seem to cause node failures consistently, though it is currently unknown which if any Vray features are to blame. The Zync Engineering team is currently tracking this issue to determine exact cause. If you have any issues using 64-core machines please write us at

Time limit on preflight phase

For some jobs like Houdini or Renderman before the actual rendering there is a preflight. In the preflight intermediate files are created. Ex. for Houdini, standalone files (.ifd,.ass) are created from a .hip file. It can take long time, especially when the scene contains simulations. For Renderman and Houdini limit is 2h.
Note: For Houdini one can use file caches generated locally to make the export faster.

Lack of support for Unicode characters

Currently there is no Unicode support in Zync, neither for scenes nor for assets.

Lack of support for special characters in file paths

Valid filenames and paths must contain only lower- and upper-case ASCII characters, spaces, dashes, underscores, and periods.

Client App

The application "" can't be opened

This can happen when upgrading to the latest version of the Zync Client App. It's caused by a bug in OS X which causes older application data to hang around.

If you get this error message, follow this procedure:

  1. Move the entire /Applications/ZYNC directory to the trash; this uninstalls the Zync Client App.
  2. Restart your computer; this clears the OS X cache which causes this error.
  3. Reinstall the Zync Client App as usual; it should now start normally.

Plugin Installer

NilObjectException on connectivity problems

If your workstation does not meet the requirement for direct connectivity to the World Wide Web, then the plugin installer crashes with NilObjectException after choosing which application to set up Zync Plugins for.

The Zync engineering team is working on fixing this. In the meantime, two workarounds are available:


Error when using old Mantra nodes

Before rendering make sure, that Mantra node used for rendering is created with the same version of Houdini that you are using to send the job. If there is mismatch of the versions, your job can error due to incompatible parameters contained by the node.

Spaces in paths

Zync jobs may crash when project filename, output directory path or output filename contains space. In the docs of Houdini ( one can read: "Avoid using spaces in filenames. Although most operating systems support them, many software packages (including Houdini!) sometimes assume that filenames don’t have spaces, and this can cause a lot of trouble. Use CamelCase or under_scores instead.".

Python version on CentOS

Some users of CentOS are having outdated python version. One of the known issues of python 2.7.5 is lack of '_create_default_https_context' function in ssl package. To detect your python version open Windows->Python shell (Alt+Shift+P), the python version should be printed in the first line in the shell. Make sure your version is not older than 2.7.6.