I'm new to eclipse, I want to install JPA plugging so I can benefit of the JPA wizard and import entity classes easily ... I tried to download it using eclipse install software menu using eclipse juno repository, I found many links, I tried to download them all, but during the downloading, I get an error saying 'installing software' has encountered a problem, An error occurred while collecting items to be installed :

```
An error occurred while collecting items to be installed
session context was:(profile=SDKProfile, phase=org.eclipse.equinox.internal.p2.engine.phases.Collect, operand=, action=).
No repository found containing: osgi.bundle,commonj.sdo,2.1.1.v201112051852
No repository found containing: osgi.bundle,javax.activation,1.1.0.v201108011116
No repository found containing: osgi.bundle,javax.mail,1.4.0.v201005080615
No repository found containing: osgi.bundle,javax.persistence,2.0.4.v201112161009
No repository found containing: osgi.bundle,javax.persistence,2.0.5.v201212031355
No repository found containing: osgi.bundle,javax.servlet,2.4.0.v200806031604
No repository found containing: osgi.bundle,javax.ws.rs,1.1.1.v20101004-1200
No repository found containing: osgi.bundle,javax.wsdl,1.6.2.v201012040545
No repository found containing: osgi.bundle,javax.xml.bind,2.2.0.v201105210648
No repository found containing: osgi.bundle,javax.xml.stream,1.0.1.v201004272200
No repository found containing: osgi.bundle,org.apache.commons.collections,3.2.0.v201005080500
No repository found containing: osgi.bundle,org.apache.commons.lang,2.1.0.v201005080500
No repository found containing: osgi.bundle,org.apache.velocity,1.5.0.v200905192330
No repository found containing: osgi.bundle,org.eclipse.jem,2.0.600.v201201051400
No repository found containing: osgi.bundle,org.eclipse.jem.workbench,2.0.400.v201104251400
No repository found containing: osgi.bundle,org.eclipse.jpt.common.branding,1.2.1.v201208222210
No repository found containing: osgi.bundle,org.eclipse.jpt.common.core,1.2.2.v201301082148
No repository found containing: osgi.bundle,org.eclipse.jpt.common.eclipselink.branding,1.2.1.v201208222210
No repository found containing: osgi.bundle,org.eclipse.jpt.common.eclipselink.core,1.2.1.v201208222210
No repository found containing: org.eclipse.update.feature,org.eclipse.jpt.common.eclipselink.feature,1.2.1.v201208222210-3318s73573J777753
No repository found containing: org.eclipse.update.feature,org.eclipse.jpt.common.feature,1.2.2.v201301082148-664AkF7BG7WDLFEEF
No repository found containing: osgi.bundle,org.eclipse.jpt.common.ui,1.2.1.v201208222210
No repository found containing: osgi.bundle,org.eclipse.jpt.common.utility,2.1.1.v201208222210
No repository found containing: osgi.bundle,org.eclipse.jpt.dbws.eclipselink.branding,1.1.101.v201208222210
No repository found containing: osgi.bundle,org.eclipse.jpt.dbws.eclipselink.core.gen,1.0.1.v201208222210
No repository found containing: org.eclipse.update.feature,org.eclipse.jpt.dbws.eclipselink.feature,1.1.102.v201301101606-797EBpCcNBHLEeHXGVaV4KKI
No repository found containing: osgi.bundle,org.eclipse.jpt.dbws.eclipselink.ui,1.0.201.v201208222210
No repository found containing: osgi.bundle,org.eclipse.jpt.doc.user,1.4.2.v201205290002
No repository found containing: osgi.bundle,org.eclipse.jpt.jaxb.branding,1.2.1.v201208222210
No repository found containing: osgi.bundle,org.eclipse.jpt.jaxb.core,1.2.2.v201301082148
No repository found containing: osgi.bundle,org.eclipse.jpt.jaxb.core.schemagen,1.0.201.v201208222210
No repository found containing: osgi.bundle,org.eclipse.jpt.jaxb.eclipselink.branding,1.2.1.v201208222210
No repository found containing: osgi.bundle,org.eclipse.jpt.jaxb.eclipselink.core,1.2.1.v201208222210
No repository found containing: osgi.bundle,org.eclipse.jpt.jaxb.eclipselink.core.schemagen,1.1.1.v201208222210
No repository found containing: org.eclipse.update.feature,org.eclipse.jpt.jaxb.eclipselink.feature,1.3.2.v201301092252-777B5BgJ9EJAgHNGrMm1f9e
No repository found containing: osgi.bundle,org.eclipse.jpt.jaxb.eclipselink.ui,1.3.1.v201208222210
No repository found containing: org.eclipse.update.feature,org.eclipse.jpt.jaxb.feature,1.2.2.v201301082148-56ACAkF7BG7WDLFEEF
No repository found containing: osgi.bundle,org.eclipse.jpt.jaxb.ui,1.3.1.v201208222210
No repository found containing: osgi.bundle,org.eclipse.jpt.jpa.branding,3.2.1.v201208222210
No repository found containing: osgi.bundle,org.eclipse.jpt.jpa.core,3.2.2.v201301092252
No repository found containing: osgi.bundle,org.eclipse.jpt.jpa.db,2.1.101.v201208222210
No repository found containing: osgi.bundle,org.eclipse.jpt.jpa.db.ui,2.0.1.v201208222210
No repository found containing: osgi.bundle,org.eclipse.jpt.jpa.eclipselink.branding,3.2.1.v201208222210
No repository found containing: osgi.bundle,org.eclipse.jpt.jpa.eclipselink.core,2.2.1.v201208222210
No repository found containing: osgi.bundle,org.eclipse.jpt.jpa.eclipselink.core.ddlgen,2.1.1.v201208222210
No repository found containing: org.eclipse.update.feature,org.eclipse.jpt.jpa.eclipselink.feature,3.2.2.v201301082148-7K7J78EVVFNVHz0NgOXgX4KKI
No repository found containing: osgi.bundle,org.eclipse.jpt.jpa.eclipselink.ui,2.2.1.v201208222210
No repository found containing: org.eclipse.update.feature,org.eclipse.jpt.jpa.feature,3.2.2.v201301091616-7U7K8qFC7sRdwVKaof36y4KKI
No repository found containing: osgi.bundle,org.eclipse.jpt.jpa.gen,2.2.2.v201301082148
No repository found containing: osgi.bundle,org.eclipse.jpt.jpa.ui,3.2.2.v201301092252
No repository found containing: osgi.bundle,org.eclipse.jst.common.annotations.controller,1.1.300.v200908252030
No repository found containing: osgi.bundle,org.eclipse.jst.common.annotations.core,1.1.300.v201004141630
No repository found containing: osgi.bundle,org.eclipse.jst.common.frameworks,1.1.601.v201208160700
No repository found containing: osgi.bundle,org.eclipse.jst.common.project.facet.core,1.4.201.v201108161900
No repository found containing: osgi.bundle,org.eclipse.jst.common.project.facet.ui,1.4.200.v201008182133
No repository found containing: osgi.bundle,org.eclipse.jst.common.ui,1.0.201.v201208292200
No repository found containing: osgi.bundle,org.eclipse.jst.j2ee,1.1.603.v201301092200
No repository found containing: osgi.bundle,org.eclipse.jst.j2ee.core,1.2.200.v201205030130
No repository found containing: osgi.bundle,org.eclipse.jst.j2ee.ejb,1.1.601.v201210040812
No repository found containing: osgi.bundle,org.eclipse.jst.j2ee.ejb.annotation.model,1.1.300.v201003112036
No repository found containing: osgi.bundle,org.eclipse.jst.j2ee.jca,1.1.600.v201111012200
No repository found containing: osgi.bundle,org.eclipse.jst.j2ee.ui,1.1.600.v201205170400
No repository found containing: osgi.bundle,org.eclipse.jst.j2ee.web,1.1.601.v201212130700
No repository found containing: osgi.bundle,org.eclipse.jst.jee,1.0.501.v201301091334
No repository found containing: osgi.bundle,org.eclipse.jst.server.core,1.2.302.v20120503_1042
No repository found containing: osgi.bundle,org.eclipse.persistence.antlr,3.2.0.v201206041011
No repository found containing: osgi.bundle,org.eclipse.persistence.antlr.source,3.2.0.v201206041011
No repository found containing: osgi.bundle,org.eclipse.persistence.asm,3.3.1.v201206041142
No repository found containing: osgi.bundle,org.eclipse.persistence.asm.source,3.3.1.v201206041142
No repository found containing: osgi.bundle,org.eclipse.persistence.core,2.4.1.v20121003-ad44345
No repository found containing: osgi.bundle,org.eclipse.persistence.core,2.4.2.v20121206-a9d0e8d
No repository found containing: osgi.bundle,org.eclipse.persistence.core.source,2.4.1.v20121003-ad44345
No repository found containing: osgi.bundle,org.eclipse.persistence.dbws,2.4.1.v20121003-ad44345
No repository found containing: osgi.bundle,org.eclipse.persistence.dbws,2.4.2.v20121206-a9d0e8d
No repository found containing: osgi.bundle,org.eclipse.persistence.dbws.builder,2.4.1.v20121003-ad44345
No repository found containing: osgi.bundle,org.eclipse.persistence.dbws.builder,2.4.2.v20121206-a9d0e8d
No repository found containing: osgi.bundle,org.eclipse.persistence.dbws.builder.source,2.4.1.v20121003-ad44345
No repository found containing: org.eclipse.update.feature,org.eclipse.persistence.dbws,2.4.1.v20121003-ad44345
No repository found containing: osgi.bundle,org.eclipse.persistence.dbws.source,2.4.1.v20121003-ad44345
No repository found containing: org.eclipse.update.feature,org.eclipse.persistence.dbws.source,2.4.1.v20121003-ad44345
No repository found containing: org.eclipse.update.feature,org.eclipse.persistence.dbwsbuilder,2.4.1.v20121003-ad44345
No repository found containing: org.eclipse.update.feature,org.eclipse.persistence.dbwsbuilder.source,2.4.1.v20121003-ad44345
No repository found containing: osgi.bundle,org.eclipse.persistence.jpa,2.4.1.v20121003-ad44345
No repository found containing: osgi.bundle,org.eclipse.persistence.jpa,2.4.2.v20121206-a9d0e8d
No repository found containing: osgi.bundle,org.eclipse.persistence.jpa.equinox,2.4.1.v20121003-ad44345
No repository found containing: osgi.bundle,org.eclipse.persistence.jpa.equinox.source,2.4.1.v20121003-ad44345
No repository found containing: osgi.bundle,org.eclipse.persistence.jpa.equinox.weaving,2.4.1.v20121003-ad44345
No repository found containing: osgi.bundle,org.eclipse.persistence.jpa.equinox.weaving.source,2.4.1.v20121003-ad44345
No repository found containing: org.eclipse.update.feature,org.eclipse.persistence.jpa,2.4.1.v20121003-ad44345
No repository found containing: osgi.bundle,org.eclipse.persistence.jpa.jpql,2.0.1.v20121003-ad44345
No repository found containing: osgi.bundle,org.eclipse.persistence.jpa.jpql,2.0.1.v20121206-a9d0e8d
No repository found containing: osgi.bundle,org.eclipse.persistence.jpa.jpql.source,2.0.1.v20121003-ad44345
No repository found containing: osgi.bundle,org.eclipse.persistence.jpa.jpql.source,2.0.1.v20121206-a9d0e8d
No repository found containing: osgi.bundle,org.eclipse.persistence.jpa.osgi,2.4.1.v20121003-ad44345
No repository found containing: osgi.bundle,org.eclipse.persistence.jpa.osgi.source,2.4.1.v20121003-ad44345
No repository found containing: osgi.bundle,org.eclipse.persistence.jpa.source,2.4.1.v20121003-ad44345
No repository found containing: org.eclipse.update.feature,org.eclipse.persistence.jpa.source,2.4.1.v20121003-ad44345
No repository found containing: osgi.bundle,org.eclipse.persistence.moxy,2.4.1.v20121003-ad44345
No repository found containing: osgi.bundle,org.eclipse.persistence.moxy,2.4.2.v20121206-a9d0e8d
No repository found containing: org.eclipse.update.feature,org.eclipse.persistence.moxy,2.4.1.v20121003-ad44345
No repository found containing: osgi.bundle,org.eclipse.persistence.moxy.source,2.4.1.v20121003-ad44345
No repository found containing: org.eclipse.update.feature,org.eclipse.persistence.moxy.source,2.4.1.v20121003-ad44345
No repository found containing: osgi.bundle,org.eclipse.persistence.nosql,2.4.1.v20121003-ad44345
No repository found containing: org.eclipse.update.feature,org.eclipse.persistence.nosql,2.4.1.v20121003-ad44345
No repository found containing: osgi.bundle,org.eclipse.persistence.nosql.source,2.4.1.v20121003-ad44345
No repository found containing: org.eclipse.update.feature,org.eclipse.persistence.nosql.source,2.4.1.v20121003-ad44345
No repository found containing: osgi.bundle,org.eclipse.persistence.oracle,2.4.1.v20121003-ad44345
No repository found containing: osgi.bundle,org.eclipse.persistence.oracle.source,2.4.1.v20121003-ad44345
No repository found containing: osgi.bundle,org.eclipse.persistence.oracleddlparser,1.0.0.v20120628
No repository found containing: osgi.bundle,org.eclipse.persistence.oracleddlparser.source,1.0.0.v20120628
No repository found containing: org.eclipse.update.feature,org.eclipse.persistence.sdk,2.4.1.v20121003-ad44345
No repository found containing: osgi.bundle,org.eclipse.persistence.sdo,2.4.1.v20121003-ad44345
No repository found containing: org.eclipse.update.feature,org.eclipse.persistence.sdo,2.4.1.v20121003-ad44345
No repository found containing: osgi.bundle,org.eclipse.persistence.sdo.source,2.4.1.v20121003-ad44345
No repository found containing: org.eclipse.update.feature,org.eclipse.persistence.sdo.source,2.4.1.v20121003-ad44345
No repository found containing: osgi.bundle,org.eclipse.wst.common.project.facet.ui,1.4.300.v201111030424
No repository found containing: osgi.bundle,org.eclipse.wst.css.core,1.1.602.v201210091733
No repository found containing: osgi.bundle,org.eclipse.wst.css.ui,1.0.702.v201211262010
No repository found containing: osgi.bundle,org.eclipse.wst.html.core,1.1.602.v201301032305
No repository found containing: osgi.bundle,org.eclipse.wst.html.ui,1.0.702.v201211262010
No repository found containing: osgi.bundle,org.eclipse.wst.internet.monitor.core,1.0.505.v20110419
No repository found containing: osgi.bundle,org.eclipse.wst.jsdt.core,1.1.202.v201208171701
No repository found containing: osgi.bundle,org.eclipse.wst.jsdt.manipulation,1.0.400.v201204261600
No repository found containing: osgi.bundle,org.eclipse.wst.jsdt.ui,1.1.202.v201208171701
No repository found containing: osgi.bundle,org.eclipse.wst.server.discovery,1.0.300.v20120403_0949
No repository found containing: osgi.bundle,org.eclipse.wst.server.ui,1.4.100.v20121112_1718
No repository found containing: osgi.bundle,org.eclipse.wst.web,1.1.600.v201204190200
No repository found containing: osgi.bundle,org.eclipse.wst.web.ui,1.1.600.v201109220400
No repository found containing: osgi.bundle,org.jdom,1.0.0.v201005080400

```

What I should I do to get this fixed, I should precise that I downloaded an offline version but I couldn't know how to integrate it, please clarify things to me.