Really weird eclipse keyboard behavior/bug?

Question

I am using Helios on Mac Snow Leopard. I don\'t know why but all of a sudden my arrow keys and delete button start not working only on Eclipse (so Eclipse ignores them) but

Answer 1

For me, the root cause was my mouse.

Backspace and navigation keys did not work. I could fix this temporarily by manually setting the key bindings as described on this page.

The root cause and permanent solution was fixing the stuck 3rd mouse button on my Evoluent Vertical Grip mouse. Since I never used that button, I didn't notice that it was permanently engaged, probably from the mouse sliding off the desk on to the ground one too many times. Once I was able to get the button unstuck, the problem was solved immediately.

This was really frustrating. I spent weeks wondering why it was happening and sporadically searching the web for answers. Of course I had a temporary solution, but the fact that it kept happening was annoying. I tried reinstalling Eclipse from scratch, trying different versions and switching workspaces, but nothing worked. I'm surprised it ended up being a stuck mouse button after all that.