eclipse mars installation problems "artifact not found"

[Fred Richardson]

I've been using Emacs+ for years with Indigo and I'm trying out the much newer mars on 64bit Linux

I deleted my previous ~/.eclipse directory, and launched with a new workspace.

I get the following error trying to install Emacs+

eclipse.buildId=4.5.1.M20150904-0015
java.version=1.7.0_40
java.vendor=Oracle Corporation
BootLoader constants: OS=linux, ARCH=x86_64, WS=gtk, NL=en_US
Framework arguments:  -product org.eclipse.epp.package.rcp.product
Command-line arguments:  -data file:/home/frichard/workspace-mars/ -os linux -ws gtk -arch x86_64 -product org.eclipse.epp.package.rcp.product

org.eclipse.equinox.p2.ui
Error
Wed Nov 04 14:38:27 EST 2015
Artifact not found: http://www.mulgasoft.com/emacsplus/e4/update-site/content.jar.

org.eclipse.equinox.p2.core.ProvisionException: Artifact not found: http://www.mulgasoft.com/emacsplus/e4/update-site/content.jar.
    at org.eclipse.equinox.internal.p2.repository.CacheManager.updateCache(CacheManager.java:428)
    at org.eclipse.equinox.internal.p2.repository.CacheManager.createCache(CacheManager.java:259)
    at org.eclipse.equinox.internal.p2.metadata.repository.SimpleMetadataRepositoryFactory.getLocalFile(SimpleMetadataRepositoryFactory.java:66)
    at org.eclipse.equinox.internal.p2.metadata.repository.SimpleMetadataRepositoryFactory.load(SimpleMetadataRepositoryFactory.java:88)
    at org.eclipse.equinox.internal.p2.metadata.repository.MetadataRepositoryManager.factoryLoad(MetadataRepositoryManager.java:57)
    at org.eclipse.equinox.internal.p2.repository.helpers.AbstractRepositoryManager.loadRepository(AbstractRepositoryManager.java:768)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at org.eclipse.oomph.util.ReflectUtil.invokeMethod(ReflectUtil.java:116)
    at org.eclipse.oomph.p2.internal.core.CachingRepositoryManager.loadRepository(CachingRepositoryManager.java:337)
    at org.eclipse.oomph.p2.internal.core.CachingRepositoryManager.loadRepository(CachingRepositoryManager.java:144)
    at org.eclipse.oomph.p2.internal.core.CachingRepositoryManager$Metadata.loadRepository(CachingRepositoryManager.java:387)
    at org.eclipse.equinox.internal.p2.metadata.repository.MetadataRepositoryManager.loadRepository(MetadataRepositoryManager.java:96)
    at org.eclipse.equinox.internal.p2.metadata.repository.MetadataRepositoryManager.loadRepository(MetadataRepositoryManager.java:92)
    at org.eclipse.equinox.p2.ui.ProvisioningUI.loadMetadataRepository(ProvisioningUI.java:440)
    at org.eclipse.equinox.internal.p2.ui.model.MetadataRepositoryElement.getMetadataRepository(MetadataRepositoryElement.java:126)
    at org.eclipse.equinox.internal.p2.ui.model.MetadataRepositoryElement.getRepository(MetadataRepositoryElement.java:115)
    at org.eclipse.equinox.internal.p2.ui.model.MetadataRepositoryElement.getQueryable(MetadataRepositoryElement.java:109)
    at org.eclipse.equinox.internal.p2.ui.QueryProvider.getQueryDescriptor(QueryProvider.java:88)
    at org.eclipse.equinox.internal.p2.ui.model.QueriedElement.fetchChildren(QueriedElement.java:101)
    at org.eclipse.equinox.internal.p2.ui.model.MetadataRepositoryElement.fetchChildren(MetadataRepositoryElement.java:77)
    at org.eclipse.equinox.internal.p2.ui.model.RemoteQueriedElement.fetchDeferredChildren(RemoteQueriedElement.java:34)
    at org.eclipse.ui.progress.DeferredTreeContentManager$1.run(DeferredTreeContentManager.java:232)
    at org.eclipse.core.internal.jobs.Worker.run(Worker.java:55)
Caused by: java.io.FileNotFoundException: http://www.mulgasoft.com/emacsplus/e4/update-site/content.jar
    at org.eclipse.equinox.internal.p2.transport.ecf.RepositoryStatusHelper.checkFileNotFound(RepositoryStatusHelper.java:297)
    at org.eclipse.equinox.internal.p2.transport.ecf.FileReader.checkException(FileReader.java:478)
    at org.eclipse.equinox.internal.p2.transport.ecf.FileReader.sendRetrieveRequest(FileReader.java:435)
    at org.eclipse.equinox.internal.p2.transport.ecf.FileReader.readInto(FileReader.java:358)
    at org.eclipse.equinox.internal.p2.transport.ecf.RepositoryTransport.download(RepositoryTransport.java:101)
    at org.eclipse.oomph.p2.internal.core.CachingTransport.download(CachingTransport.java:149)
    at org.eclipse.oomph.p2.internal.core.CachingTransport.download(CachingTransport.java:204)
    at org.eclipse.equinox.internal.p2.repository.CacheManager.updateCache(CacheManager.java:402)
    ... 25 more

[Fred Richardson]

Anyone else able to install Emacs+ in Eclipse Mars or later?