Debug issues related to the Talend Studio error 'Could not find or load main class'

Problem Description

A Talend Studio Job fails to start with the following error message:

Starting job test at 07:15 27/11/2019.

Error: Could not find or load main class myproject.test_0_1.test

Job test ended at 07:15 27/11/2019. [exit code=1]


Root Cause

In this case, the wrong JAR file is in the Maven repository. 



This article provides a method to get more details about the potential cause of the error.


  1. In Talend Studio navigate to, Window > Show view...



  2. Add the following views:

    • General > Error Log

    • General > Problems

    • Talend > Problems

  3. Delete any errors that may already exist in the three views.

  4. Reproduce the issue, then check each view for new errors.


For a demonstration, review the studio_debug_classnotfound.mp4 video file (attached to this article).

Version history
Revision #:
3 of 3
Last update:
‎12-05-2019 08:13 AM
Updated by: