"java.net.SocketException: Permission denied: connect" when opening a Desktop Automation robot

Issue

Desktop Automation robot fails to open in Design Studio and throws an Internal Error. Stack trace of the error includes

com.kapowtech.lang.ApplicationError: Internal error during robot execution.
    at kapow.robot.robomaker.engine.design.DesignExecutionController$DesignModeExecutionControllerEngineCallback$1.run(DesignExecutionController.java:446)
[...]
Caused by: com.kapowtech.lang.ApplicationError: Could not start the local Automation Service
    at kapow.robot.plugin.common.stepaction.rl2.LocalHubProvider.initialize(LocalHubProvider.java:147)
    at kapow.robot.robomaker.engine.AbstractRobotExecutionEngine.initializeLocalAndRemoteHubs(AbstractRobotExecutionEngine.java:239)
    at kapow.robot.robomaker.engine.design.full.FullExecutionRobotExecutionEngine.initExecution(FullExecutionRobotExecutionEngine.java:190)
    at kapow.robot.robomaker.engine.StudioRobotExecutionEngine.lambda$startBackgroundExecution$0(StudioRobotExecutionEngine.java:267)
    ... 1 more
Caused by: com.kapowtech.hub.HubException: connection failed, or time out occurred while connecting
    at com.kapowtech.hub.Connection.<init>(Connection.java:77)
    at com.kapowtech.hub.Connection.<init>(Connection.java:90)
    at com.kapowtech.hub.LocalHub.<init>(LocalHub.java:131)
    at kapow.robot.plugin.common.stepaction.rl2.LocalHubProvider.initialize(LocalHubProvider.java:123)
    ... 4 more
Caused by: java.net.SocketException: Permission denied: connect
[...]

Solution

This error can occur in environments where a VPN or firewall blocks the access of the Desktop Automation service to the local IPs.
As a first step, to confirm this is the issue, disable VPN/firewall and check again.
If the robot works without the VPN/firewall but they have to be enabled (e.g. company policy, they are needed for other access) then a possible workaround is to add the following line

wrapper.java.additional.1 = -Djava.net.preferIPv4Stack = true

to the common.conf file - which is located in the Design Studio installation folder under bin.
Note: if wrapper.java.additional.1 exists, use the next available id.

Restart Design Studio after editing and saving this file.

If this still doesn't fix the error please open a support case on the Customer Portal.

Level of Complexity 

Moderate

Applies to  

References

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