TestNG An internal error occurred during launching

I encountered a problem with similar symptoms today. I'm not sure if it is the same problem but it matches everything in your question.

In my case, the log files said:

!ENTRY org.eclipse.core.jobs 4 2 2015-12-03 15:49:19.369
!MESSAGE An internal error occurred during: "Launching NewTest".
!STACK 0
java.lang.NullPointerException
at org.testng.eclipse.maven.MavenTestNGLaunchConfigurationProvider.getVMArgsFromPom(MavenTestNGLaunchConfigurationProvider.java:74)

So my problem was that the TestNG-plugin in Eclipse failed to find the pom-file, as I don't use Maven. Anyway, after uninstalling the optional M2E (Maven...) part of the TestNG Eclipse plugin I could run my TestNG test cases successfully.

If you have the same issue, you uninstall the M2E part in Eclipse by selecting

• Help
• Install new software...
• What is already installed?
• Select the TestNG M2E software and click uninstall

Hope this helps!

Need to uninstall M2E. I uninstalled like below path: Help->Install new software->Already installed -> Uninstall M2E

I Installed TestNG in Eclipse and tried to execute test case but got error message "Launching Test Case has encountered a problem, an Internal error occur during during launching Test Case "

i guess TestNG-plugin in Eclipse might failed,i uninstalled optional M2E (Maven...). After uninstalling the optional M2E (Maven...) part of the TestNG Eclipse plugin I could run my TestNG test cases successfully.

If you have the same issue, you uninstall the M2E part in Eclipse by selecting

Help Install new software... What is already installed? Select the TestNG M2E software and click uninstall

I was also getting the same issue, I just uninstalled TestNG M2E software.

Steps:

1. Help
2. Install new software.
3. Install/Update.
4. Click on Install/Update link (right-hand side)
5. Select TestNG M2E from the list.
6. Uninstall.