error - in one project is stopping other projects from running

Greetings -

very new to JAVA and NetBeans -

I have just started a project and it has an error the red underline is on some code that has worked in an earlier example.

I closed that project and opened one that has worked.

I'm now getting the error:

Exception in thread "main" java.lang.RuntimeException: Uncompilable source code
at open_url.Main.main(Main.java:37)

When I try to run other projects including the simple "Hello World"

The error is in the Main - of another project.

When I click one the Main.java:37 link within the error, NetBeans opens the other "Main" file within the project "Open_URL"

How / Why are these projects that have worked now being linked or pointed to this new main with the error in in?

How can I unlink them / tell the project to quit looking at the file?

What info can I provide to help ask this question better?

Thanks
Sparky

I do notice that the project (Open_URL) is more bold in the left hand list than the other projects (in NetBeans) - the main.java within Open_URL is the place that ALL of my other projects are pointing to for the error. - It appears ALL of my projects will not run (I only have 4 or 5 simple examples). They all point to line 37 of the main.java within Open_URL.

How are these getting linked or connected - how one error in one project stops everybody else?

Thanks
Sparky

Right click the project you are working on, and "set as main project". The build buttons compile the main project, so you are compiling/running something different (the one with the errors).