i recently download the Spring IDE complete download rather than download eclipse and plugin.
Hence now i goto the Update Sites and there is nothing there... so i add the following
http://download.eclipse.org/mpc/indigo/
which is noted here http://www.eclipse.org/mpc/
and try and install the market but i get the following error
Cannot complete the install because one or more required items could not be found. Software being installed: Marketplace Client 1.1.1.I20110907-0947 (org.eclipse.epp.mpc.feature.group 1.1.1.I20110907-0947) Missing requirement: Marketplace Client 1.1.1.I20110907-0947 (org.eclipse.epp.mpc.feature.group 1.1.1.I20110907-0947) requires 'org.eclipse.equinox.p2.discovery.feature.feature.group [1.0.0.v201004,2.0.0)' but it could not be found
I had the same problem. Update eclipse first using Help->Check for Updates. Then try installing the market place client.