Eclipse - An internal error occurred during: "Compute launch button tooltip"

Question

I launched Eclipse earlier to jot down a snippet and was faced with the following as an error when I tried to run a fresh project:

An internal error occurred during: "Compute launch button tooltip".

That popup window shows as soon as I mouse-over the run icon in the top bar, or if I right click on the class in the explorer window and select any of the run/debug options.

After doing some research on the error, I see several people who posted similar messages but they all have been fresh installs of Eclipse. So note that this is not a fresh install, and that Eclipse was working fine earlier today. Also note that not only does my new project not run (with the normal main method), but projects I was running earlier have all stopped working with the same error.

Finally, also be aware that after seeing other people's suggestions on fixing this, one specifically said to select run configurations from the top of the page run menu. When I selected run configurations from this dropdown, I got the following message:

Exception occurred creating launch configuration tabs
Reason: Plug-in org.eclipse.jdt.debug.ui was unable to load class org.eclipse.jdt.internal.debug.ui.launcher.LocalJavaApplicationTabGroup

After that message, the run window opens but all of the tabs are missing. Like where you can set the display width and height, and the other tabs, they are all missing from the window now.

I was using Eclipse trouble free earlier today and I am sure no updates took place between when Eclipse was working and now. My question is of multiple parts: What is wrong in a nutshell? What could have caused this?

Answer 1

Got this from another site of some guy who got this same error after upgrading. Worked for me as well. Apparently putting the following line in your eclipse.ini helps:

-Dcom.ibm.icu.util.TimeZone.DefaultTimeZoneType=ICU

Answer 2

Try setting the launch properties in:

Window>Preferences>Run/Debug(Expand)>Launching(Click)

Under launch Operations menu set it to:

Always launch the previously launched application

Click:

Apply>Ok