Unable to open Eclipse from Dash Home

The cause

If you install an application via apt-get, you can be pretty sure a correct .desktop file is installed in /usr/share/applications. That leaves us the only option that there must be an outdated .desktop file, representing Eclipse, in ~/.local/share/applications, most likely of a previous locally installed version, or some application must have created a local version of the previous .desktop file.

Since local .desktop files overrule the global ones, you will have to remove it.

What to do

Run the command:

rm ~/.local/share/applications/*eclipse*

This will remove all local version(s) of the .desktop file. Subsequently log out and back in. It should be fixed.