Question

I’ve always used the Export -> Runnable jar option of Eclipse and it has worked perfectly, but today it seems that all the Runnable jars I create produce the following error when I run them: (Edit: run them by double clicking the file.)

Java Virtual Machide Launcher

Could not find the main class: (class). Program will exit.

I’ve tried everything for the past two hours, but it still doesn’t work.

• I can still run jars that I have created in the past without a
  problem.
• The manifest file looks exactly the same as in those jars
  that work and all the .class files seem to be in place…
• I’ve tried exporting with Package required libraries into generated jar but the file still doesn’t work. It doesn’t show the error though – double clicking the file does nothing.

Edit: Running the jar file through the cmd works perfectly, but simply double clicking on it yields this error. (Bragboy)

Edit 2:
Contents of a manifest file from a jar that works: (Obviously they’re the same, just wanted to avoid confusion.)

Manifest-Version: 1.0
Class-Path: .
Main-Class: defender.DefenderComponent (+ two empty lines afterwards)

And contents of a manifest file from a jar that doesn’t work: (When opening the file directly)

Manifest-Version: 1.0
Class-Path: .
Main-Class: pixel.Entry (+ two empty lines afterwards)

Both main class files are confirmed to be at their respective locations.

Answer 1

In the end the only thing that fixed this was to switch from JRE 1.7 down to JRE 1.6.