An error occurred while collecting items to be installed
session context was:(profile=C__Users_Thomas Prentice_eclipse_java-mars_eclipse, phase=org.eclipse.equinox.internal.p2.engine.phases.Collect, operand=, action=).
Unable to read repository at http://downloads.sourceforge.net/dpp/de.fu_berlin.inf.dpp_14.10.31.jar?use_mirror=dfn.
sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
Unable to read repository at http://downloads.sourceforge.net/dpp/de.fu_berlin.inf.dpp.core_0.1.0.jar?use_mirror=dfn.
sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
Unable to read repository at http://downloads.sourceforge.net/dpp/de.fu_berlin.inf.dpp.whiteboard_14.10.31.jar?use_mirror=dfn.
sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target