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"Class com.teamdev.jxbrowser.chromium.BrowserContext" Error When Opening Device / Desktop Automation Editor


Question / Problem: 

When opening Desktop Automation Editor, the top half of the UI (workflow steps) never populates and sometimes the bottom half showing the connection to the remote device may not show either. A stack trace displays as well. What causes this and how can it be resolved?

Answer / Solution: 

This issue is caused by security policies via Windows AppLocker. 

When DA workflow editor is opened (via "Edit" button in the DA step), several background processes happen in Kapow / RPA:

1. Files are expanded into the user's C:\Users\<userName>\AppData\Local\JxBrowser\browsercore-<version> folder. Most of these files relate to Chromium.
2. Within that browsercore-<version>  folder, several sub-directories are created, among those are Data and Dictionaries. Once these are created, the Editor should open without issues.

Exceptions must be configured to allow full permissions, including execution of .exe files within the user's AppData\Local as well as the Design Studio installation folder. To get a complete listing of events that occur in the JxBrowser path (to help modify your AppLocker policy), obtain a Process Monitor trace as follows:

1. Run Windows' Process Monitor ("ProcMon") - a free download from Microsoft. 
2. Enable only the file trace just before clicking "Edit" in DS (no need for Registry, Network or Thread tracing).
3. Stop the trace after clicking "Edit" and reproducing the issue.

Complete stack trace message will be something like the following:

Exception message:
Could not initialize class com.teamdev.jxbrowser.chromium.BrowserContext

Stack trace:
java.lang.NoClassDefFoundError: Could not initialize class com.teamdev.jxbrowser.chromium.BrowserContext
at java.util.concurrent.ThreadPoolExecutor.runWorker(
at java.util.concurrent.ThreadPoolExecutor$


Applies to:  

Product Version Category
Kapow / RPA 10.x

Desktop Automation

Device Automation



Author:  Satwant Singh