Please do your best to solve problems yourself before asking for help here. Check the FAQ
for answers to common questions, and try a web search if you can't find the answer
in the FAQ.
If relevant, state what you have done (including what you clicked on or typed) and what was the visible result. Explain how this is different from what you expected.
If BlueJ loads, or even just shows the initial "splash" screen with the BlueJ logo, it will have created a debug log.
The location of the debug log is normally shown in the "About BlueJ" dialog which you can access from the help menu. If you cannot see the About BlueJ dialog, you can find it:
Important: Before you proceed, please check the fields above and ensure that you have supplied
as much information as possible, in particular do not omit the debug log as it is usually essential
Failure to provide the debug log will mean that it takes longer to find a solution for your problem.