posted 17 years ago
The "internal" packages in Eclipse (like the org/eclipse/core/internal/runtime package in the error message here) are supposed to be private to the Eclipse platform itself, and extensions and plugins are not supposed to use them. That's because they change or even disappear quite regularly with new Eclipse releases. It looks like what happened here is that your PHP plugin authors did a naughty thing and used an internal class that is not present in the version of Eclipse that you have, so their editor is failing to load. What you need to do is check the documentation or website for the PHP plugin and see if you can figure out what version of Eclipse it works with, then try to find and install that version instead of whatever you have now. You could also report this to them as a bug, if the plugin is still being developed.