Java Extension for Unattended Robot ( No Uipath Studio )

I would like to ask for your help.

I have build a bot that manipulates a Java window application. It work on my end however when I tried to run in on an Unattended Robot, I get an error saying Target Java application cannot be accessed even though it is open in the background.

So I am thinking this could be with Java Extension.

How can we install Java extension in an unattended robot that does not have UiPath Studio installed but only UiPath Robot.

I saw the article in UiPath Docs however it seems to work only for machines that has UiPath Studio installed on it.

Any help will be greatly appreciated.

Thank you!


The main thing that the installer does is copying files into the JRE folder. Let’s suppose you have a JRE on the unattended robot machine and a folder where nuget packages are unpacked on that machine, usually it’s C:\Users\<your-user>\.nuget\packages\uipath\<uipath-version>\build\UiPath

  1. Get the files UiPathJavaBridgeImplV8.dll and UiPathJavaBridgeImplV8_x64.dll and place them in JRE\bin folder
  2. Get the file UiPathBrdge.jar from \JavaSupport subfolder inside unpacking folder and place it in the HRE\lib folder.
  3. Final step, inside JRE\lib folder, create a file called (no .txt extension) and add a line: assistive_technologies=UiPath.UiPathBridge.

The installer does all these steps and registers some keys in the registry but one can do it manually. Also, for Java 9+, there is nothing automated that can install your extension so it’s not something unusual to do it manually.

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Hello Vlad,
Thank you so much for your time on responding my query. I have installed it already.
Good thing the SetupExtensions.exe file was present in the Unattended Robot found in C:\Program Files (x86)\UiPath\Studio\UiPath

I am not sure if this is by default or that UiPath Studio was installed there before. I am new to the project so there were RPA Developers before so I am not certain.