When installing groovy plugin for eclipse 3.6 (Helios) on my Vista 64 bit, I got this error:
An error occurred while collecting items to be installed
session context was:(profile=epp.package.jee, phase=org.eclipse.equinox.internal.p2.engine.phases.Collect, operand=, action=).
Artifact not found: osgi.bundle,org.eclipse.jdt.core,3.6.2.xx-20110310-1500-e36.
http://dist.springsource.org/release/GRECLIPSE/e3.6/plugins/org.eclipse.jdt.core_3.6.2.xx-20110310-1500-e36.jar
Artifact not found: osgi.bundle,org.codehaus.groovy,1.7.8.xx-20110310-1500-e36.
http://dist.springsource.org/release/GRECLIPSE/e3.6/plugins/org.codehaus.groovy_1.7.8.xx-20110310-1500-e36.jar
Artifact not found: osgi.bundle,org.eclipse.jdt.core.source,3.6.2.xx-20110310-1500-e36.
http://dist.springsource.org/release/GRECLIPSE/e3.6/plugins/org.eclipse.jdt.core.source_3.6.2.xx-20110310-1500-e36.jar
Artifact not found: osgi.bundle,org.eclipse.jdt.groovy.core,2.1.2.xx-20110310-1500-e36.
http://dist.springsource.org/release/GRECLIPSE/e3.6/plugins/org.eclipse.jdt.groovy.core_2.1.2.xx-20110310-1500-e36.jar