I just downloaded Eclipse SDK 3.5.1 and want to install some add ons such as GEF, EMF, etc.
I downloaded all the zip files for everything I needed and decided to install them in the dropins folder. I read http://wiki.eclipse.org/Equinox_p2_Getting_Started and structured my dropin folder as specified:
eclipse/
dropins/
emf/
eclipse/
features/
plugins/
gef/
eclipse/
features/
plugins/
... etc ...
When I start up Eclipse it does not recognize any of the features or plugins I have put into the structure above. Any ideas?
I suggest that you try to install those features via the update manager. EMF and GEF are standard features from Eclipse.org, there's no reason not to install them in Eclipse's main p2 repository folder (it is easy to uninstall them, in case that is your concern).
Have a look at the error log view (Window -> Show View -> Error Log) to see why they didn't load. My guess is that they are missing a dependency, but without more information it is difficult to answer your question. I also suggest looking at Help -> About Eclipse -> Installation Details to see what exactly is installed.