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Cura will not start Slicing (OpenVPN conflict)


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Posted · Cura will not start Slicing (OpenVPN conflict)


I noticed a consistent and reproducible issue on my Mac running Cura 4.4.1


Whenever I am connected to an OpenVPN connection (how I sometimes connect to OctoPi/OctoPrint) Cura will not start the slicing process.

The following errors will show in the logs :



2020-01-07 13:02:55,116 - DEBUG - [MainThread] UM.View.GL.ShaderProgram.load [56]: Loading shader file [/Applications/Ultimaker Cura.app/Contents/MacOS/resources/shaders/transparent_object.shader]...
2020-01-07 13:02:57,654 - INFO - [MainThread] CuraEngineBackend.CuraEngineBackend.slice [225]: Starting to slice...
2020-01-07 13:02:57,654 - DEBUG - [MainThread] CuraEngineBackend.CuraEngineBackend.slice [243]: Going to slice build plate [0]!
2020-01-07 13:02:57,662 - WARNING - [Thread-4] UM.Decorators.deprecated_function [19]: <function GlobalStack.extruders at 0x600004b14f48> is deprecated (since 4.4): Please use extruderList instead.
2020-01-07 13:02:58,110 - DEBUG - [MainThread] CuraEngineBackend.CuraEngineBackend._onStartSliceCompleted [429]: Sending slice message took 0.45583605766296387 seconds
2020-01-07 13:02:58,120 - DEBUG - [Thread-21] UM.Backend.Backend._backendLog [101]: [Backend] [ERROR] Could not connect to the given address
2020-01-07 13:02:58,120 - DEBUG - [MainThread] CuraEngineBackend.CuraEngineBackend._onBackendQuit [829]: Backend quit with return code 0. Resetting process and socket.


Now that I've determined that it is an OpenVPN connection causing the issue, I've been able to reliably work around it by disconnecting my VPN before slicing.  I was just curious if there was something I could do to get them to play nice together.


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