problem installing eclipse plugin

following the guide https://developer.garmin.com/connect-iq/programmers-guide/getting-started/ to install the Connect IQ eclipse plugin version 2.3.3 leads to following 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=).
No repository found containing: osgi.bundle,IQ_AppSettingsEditor,2.3.3
No repository found containing: osgi.bundle,IQ_IDE,2.3.3
No repository found containing: osgi.bundle,IQ_PackageWizard,2.3.3
No repository found containing: osgi.bundle,IQ_SdkManager,2.3.3
No repository found containing: org.eclipse.update.feature,connectiq.feature.ide,2.3.3
No repository found containing: org.eclipse.update.feature,connectiq.feature.sdk,2.3.3