Ivy Dependency resolution fails for new Project in Eclipse

Hi! I am Using Eclipse Kepler on Windows, and I installed the IvyDE and the Vaadin plugins.

Now I tried to create a new vaadin project, but the dependency resolution after the project creation failed with the following error message:

Some projects fail to be resolved
Impossible to resolve dependencies of com.example#v7proj;working@myhostname
download failed: com.vaadin.external.google#guava;16.0.1.vaadin1!guava.jar
download failed: com.vaadin.external.atmosphere#atmosphere-runtime;2.1.2.vaadin3!atmosphere-runtime.jar(bundle)
download failed: com.vaadin#vaadin-server;7.3.0.rc1!vaadin-server.jar
download failed: com.vaadin#vaadin-sass-compiler;0.9.9!vaadin-sass-compiler.jar
Impossible to resolve dependencies of com.example#v7proj;working@myhostname
download failed: com.vaadin.external.google#guava;16.0.1.vaadin1!guava.jar
download failed: com.ibm.icu#icu4j;50.1.1!icu4j.jar
download failed: org.apache.httpcomponents#httpclient;4.3.1!httpclient.jar
download failed: xerces#xercesImpl;2.11.0!xercesImpl.jar
download failed: com.vaadin#vaadin-client;7.3.0.rc1!vaadin-client.jar
download failed: com.vaadin#vaadin-server;7.3.0.rc1!vaadin-server.jar
download failed: org.eclipse.jetty.orbit#javax.mail.glassfish;1.4.1.v201005082020!javax.mail.glassfish.jar(orbit)
download failed: com.vaadin#vaadin-sass-compiler;0.9.9!vaadin-sass-compiler.jar
download failed: com.vaadin#vaadin-sass-compiler;0.9.9!vaadin-sass-compiler.jar
Impossible to resolve dependencies of com.example#v7proj;working@myhostname
download failed: com.vaadin.external.google#guava;16.0.1.vaadin1!guava.jar
download failed: com.ibm.icu#icu4j;50.1.1!icu4j.jar
download failed: org.apache.httpcomponents#httpclient;4.3.1!httpclient.jar
download failed: xerces#xercesImpl;2.11.0!xercesImpl.jar
download failed: com.vaadin#vaadin-client;7.3.0.rc1!vaadin-client.jar
download failed: com.vaadin#vaadin-server;7.3.0.rc1!vaadin-server.jar
download failed: org.eclipse.jetty.orbit#javax.mail.glassfish;1.4.1.v201005082020!javax.mail.glassfish.jar(orbit)
download failed: com.vaadin#vaadin-sass-compiler;0.9.9!vaadin-sass-compiler.jar

If it helps, I am behind a Proxy, but this proxy is configured in Eclipse and eclipse succeeds in downloading all kinds of Packages.

Does anyone know why automatic download doesn’t work and how I could fix it?

Solved by adding a System-Wide Environment variable called

ANT_OPTS with the content

-Dhttp.proxyHost=proxy.example.com -Dhttp.proxyPort=8080 -Dhttp.proxyUser=me -Dhttp.proxyPassword=mypassword