Hi,
I hace encountered the following error while installing Force.com IDE in eclipse 3.6 

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=).
Multiple problems occurred while downloading.
Problems downloading artifact: osgi.bundle,org.eclipse.jst.common.frameworks,1.1.403.v201012160000.
Unpacking fails because intermediate file is empty: C:\DOCUME~1\299028\LOCALS~1\Temp\work4156391723566006466\p2.optimizers.incoming5554674595698595770.jar
Unable to read repository at http://download.eclipse.org/releases/helios/201102250900/aggregate/plugins/org.eclipse.jst.common.frameworks_1.1.403.v201012160000.jar.
Read timed out
Multiple problems occurred while downloading.
Problems downloading artifact: osgi.bundle,org.eclipse.jst.common.ui,1.0.3.v201101101700.
Unpacking fails because intermediate file is empty: C:\DOCUME~1\299028\LOCALS~1\Temp\work4219688490303160469\p2.optimizers.incoming2672154805032333935.jar
Unable to read repository at http://ftp.neu.edu.cn/mirrors/eclipse/releases/helios/201102250900/aggregate/plugins/org.eclipse.jst.common.ui_1.0.3.v201101101700.jar.
Read timed out
Multiple problems occurred while downloading.
Problems downloading artifact: osgi.bundle,org.eclipse.jst.j2ee.core,1.2.4.v201102101900.
Unpacking fails because intermediate file is empty: C:\DOCUME~1\299028\LOCALS~1\Temp\work7740751923448050223\p2.optimizers.incoming5284717371190109306.jar
Unable to read repository at http://ftp.cs.pu.edu.tw/pub/eclipse/releases/helios/201102250900/aggregate/plugins/org.eclipse.jst.j2ee.core_1.2.4.v201102101900.jar.
Read timed out
Multiple problems occurred while downloading.
Problems downloading artifact: osgi.bundle,org.eclipse.jst.jee,1.0.302.v201101122300.
Unpacking fails because intermediate file is empty: C:\DOCUME~1\299028\LOCALS~1\Temp\work812154278832794334\p2.optimizers.incoming8526438693230391506.jar
Unable to read repository at http://download.eclipse.org/releases/helios/201102250900/aggregate/plugins/org.eclipse.jst.jee_1.0.302.v201101122300.jar.
Read timed out
Multiple problems occurred while downloading.
Problems downloading artifact: osgi.bundle,org.eclipse.jst.jsp.core,1.2.304.v201102160550.
Unpacking fails because intermediate file is empty: C:\DOCUME~1\299028\LOCALS~1\Temp\work4490939944298773861\p2.optimizers.incoming6354730458678918067.jar
Unable to read repository at http://download.eclipse.org/releases/helios/201102250900/aggregate/plugins/org.eclipse.jst.jsp.core_1.2.304.v201102160550.jar.
Read timed out
Multiple problems occurred while downloading.
Problems downloading artifact: osgi.bundle,org.eclipse.jst.jsp.ui,1.1.503.v201101262228.
Unpacking fails because intermediate file is empty: C:\DOCUME~1\299028\LOCALS~1\Temp\work2276594139202254706\p2.optimizers.incoming4943259299808047201.jar
Unable to read repository at http://download.eclipse.org/releases/helios/201102250900/aggregate/plugins/org.eclipse.jst.jsp.ui_1.1.503.v201101262228.jar.
Read timed out
Multiple problems occurred while downloading.
Problems downloading artifact: osgi.bundle,org.eclipse.wst.common.emfworkbench.integration,1.2.3.v201012020600.
Unpacking fails because intermediate file is empty: C:\DOCUME~1\299028\LOCALS~1\Temp\work1929460959618698436\p2.optimizers.incoming1816592640553303119.jar
Unable to read repository at http://download.eclipse.org/releases/helios/201102250900/aggregate/plugins/org.eclipse.wst.common.emfworkbench.integration_1.2.3.v201012020600.jar.
Read timed out
Multiple problems occurred while downloading.
Problems downloading artifact: osgi.bundle,org.eclipse.wst.common.modulecore,1.2.5.v201101270100.
Unpacking fails because intermediate file is empty: C:\DOCUME~1\299028\LOCALS~1\Temp\work293619304186834783\p2.optimizers.incoming7921578674788273044.jar
Unable to read repository at http://mirror.switch.ch/eclipse/releases/helios/201102250900/aggregate/plugins/org.eclipse.wst.common.modulecore_1.2.5.v201101270100.jar.
Read timed out
Multiple problems occurred while downloading.
Problems downloading artifact: osgi.bundle,org.eclipse.wst.common.modulecore.ui,1.0.4.v201101101700.
Unpacking fails because intermediate file is empty: C:\DOCUME~1\299028\LOCALS~1\Temp\work4145601168816464016\p2.optimizers.incoming9174817561811997738.jar
Unable to read repository at http://mirror.switch.ch/eclipse/releases/helios/201102250900/aggregate/plugins/org.eclipse.wst.common.modulecore.ui_1.0.4.v201101101700.jar.
Read timed out
Multiple problems occurred while downloading.
Problems downloading artifact: osgi.bundle,org.eclipse.wst.common.project.facet.ui,1.4.103.v201101271715.
Unpacking fails because intermediate file is empty: C:\DOCUME~1\299028\LOCALS~1\Temp\work1975891928589443659\p2.optimizers.incoming2242887091757786902.jar
Unable to read repository at http://download.eclipse.org/releases/helios/201102250900/aggregate/plugins/org.eclipse.wst.common.project.facet.ui_1.4.103.v201101271715.jar.
Read timed out
Multiple problems occurred while downloading.
Problems downloading artifact: osgi.bundle,org.eclipse.wst.css.core,1.1.402.v201102031915.
Unpacking fails because intermediate file is empty: C:\DOCUME~1\299028\LOCALS~1\Temp\work7977470943601346707\p2.optimizers.incoming8704870350386223717.jar
Unable to read repository at http://download.eclipse.org/releases/helios/201102250900/aggregate/plugins/org.eclipse.wst.css.core_1.1.402.v201102031915.jar.
Read timed out
Multiple problems occurred while downloading.
Problems downloading artifact: osgi.bundle,org.eclipse.wst.dtd.core,1.1.401.v201101122255.
Unpacking fails because intermediate file is empty: C:\DOCUME~1\299028\LOCALS~1\Temp\work1503734520000027935\p2.optimizers.incoming3473255770872631238.jar
Unable to read repository at http://download.eclipse.org/releases/helios/201102250900/aggregate/plugins/org.eclipse.wst.dtd.core_1.1.401.v201101122255.jar.
Read timed out
Multiple problems occurred while downloading.
Problems downloading artifact: osgi.bundle,org.eclipse.wst.html.core,1.1.404.v201101190004.
Unpacking fails because intermediate file is empty: C:\DOCUME~1\299028\LOCALS~1\Temp\work5930303808894727881\p2.optimizers.incoming3052930262935434399.jar
Unable to read repository at http://carroll.aset.psu.edu/pub/eclipse/releases/helios/201102250900/aggregate/plugins/org.eclipse.wst.html.core_1.1.404.v201101190004.jar.
Read timed out
Multiple problems occurred while downloading.
Problems downloading artifact: osgi.bundle,org.eclipse.wst.html.ui,1.0.504.v201101122108.
Unpacking fails because intermediate file is empty: C:\DOCUME~1\299028\LOCALS~1\Temp\work8136419634998528426\p2.optimizers.incoming8639071224559059819.jar
Unable to read repository at http://download.eclipse.org/releases/helios/201102250900/aggregate/plugins/org.eclipse.wst.html.ui_1.0.504.v201101122108.jar.
Read timed out
Multiple problems occurred while downloading.
Problems downloading artifact: osgi.bundle,org.eclipse.wst.jsdt.core,1.1.4.v201102102045.
Unpacking fails because intermediate file is empty: C:\DOCUME~1\299028\LOCALS~1\Temp\work8492186343444402272\p2.optimizers.incoming6840278897980862244.jar
Unable to read repository at http://download.eclipse.org/releases/helios/201102250900/aggregate/plugins/org.eclipse.wst.jsdt.core_1.1.4.v201102102045.jar.
Read timed out
Multiple problems occurred while downloading.
Problems downloading artifact: osgi.bundle,org.eclipse.wst.jsdt.ui,1.1.4.v201102160540.
Unpacking fails because intermediate file is empty: C:\DOCUME~1\299028\LOCALS~1\Temp\work6671675823250171836\p2.optimizers.incoming6925495090144931897.jar
Unable to read repository at http://download.eclipse.org/releases/helios/201102250900/aggregate/plugins/org.eclipse.wst.jsdt.ui_1.1.4.v201102160540.jar.
Read timed out
Multiple problems occurred while downloading.
Problems downloading artifact: osgi.bundle,org.eclipse.wst.jsdt.web.support.jsp,1.0.303.v201012160047.
Unpacking fails because intermediate file is empty: C:\DOCUME~1\299028\LOCALS~1\Temp\work8145836542407873303\p2.optimizers.incoming1184222438974093371.jar
Unable to read repository at http://mirror.bit.edu.cn/eclipse/releases/helios/201102250900/aggregate/plugins/org.eclipse.wst.jsdt.web.support.jsp_1.0.303.v201012160047.jar.
Read timed out
Multiple problems occurred while downloading.
Problems downloading artifact: osgi.bundle,org.eclipse.wst.server.core,1.1.206.v20110110.
Unpacking fails because intermediate file is empty: C:\DOCUME~1\299028\LOCALS~1\Temp\work2943476779447281518\p2.optimizers.incoming5910635185958623879.jar
Unable to read repository at http://download.eclipse.org/releases/helios/201102250900/aggregate/plugins/org.eclipse.wst.server.core_1.1.206.v20110110.jar.
Read timed out
Multiple problems occurred while downloading.
Problems downloading artifact: osgi.bundle,org.eclipse.wst.server.ui,1.1.207.v20110119.
Unpacking fails because intermediate file is empty: C:\DOCUME~1\299028\LOCALS~1\Temp\work4533558507970685994\p2.optimizers.incoming3071499092762211346.jar
Unable to read repository at http://download.eclipse.org/releases/helios/201102250900/aggregate/plugins/org.eclipse.wst.server.ui_1.1.207.v20110119.jar.
Read timed out
Multiple problems occurred while downloading.
Problems downloading artifact: osgi.bundle,org.eclipse.wst.web,1.1.402.v201012160000.
Unpacking fails because intermediate file is empty: C:\DOCUME~1\299028\LOCALS~1\Temp\work3518099648204815285\p2.optimizers.incoming3115053736440004088.jar
Unable to read repository at http://carroll.aset.psu.edu/pub/eclipse/releases/helios/201102250900/aggregate/plugins/org.eclipse.wst.web_1.1.402.v201012160000.jar.
Read timed out
Multiple problems occurred while downloading.
Problems downloading artifact: osgi.bundle,org.eclipse.wst.xml.core,1.1.503.v201102102045.
Unpacking fails because intermediate file is empty: C:\DOCUME~1\299028\LOCALS~1\Temp\work70877662571057080\p2.optimizers.incoming6562150124517004171.jar
Unable to read repository at http://eclipse.dcc.fc.up.pt/releases/helios/201102250900/aggregate/plugins/org.eclipse.wst.xml.core_1.1.503.v201102102045.jar.
Read timed out
Unable to read repository at http://www.adnsandbox.com/tools/ide/install/plugins/com.salesforce.ide_26.0.0.201210261118.jar.
Read timed out
Unable to read repository at http://www.adnsandbox.com/tools/ide/install/plugins/com.salesforce.ide.api_26.0.0.201210261118.jar.
Read timed out
Unable to read repository at http://www.adnsandbox.com/tools/ide/install/plugins/com.salesforce.ide.core_26.0.0.201210261118.jar.
Read timed out
Unable to read repository at http://www.adnsandbox.com/tools/ide/install/plugins/com.salesforce.ide.deployment_26.0.0.201210261118.jar.
Read timed out
Unable to read repository at http://www.adnsandbox.com/tools/ide/install/plugins/com.salesforce.ide.documentation_26.0.0.201210261118.jar.
Timeout while reading input stream.
The following system properties can be used to adjust the readTimeout, retryAttempts, and closeTimeout
org.eclipse.ecf.provider.filetransfer.retrieve.readTimeout=<default:1000>
org.eclipse.ecf.provider.filetransfer.retrieve.retryAttempts=<default:30>
org.eclipse.ecf.provider.filetransfer.retrieve.closeTimeout=<default:1000>

Unable to read repository at http://download.eclipse.org/releases/helios/201102250900/aggregate/features/org.eclipse.jst.web_core.feature_3.2.3.v201102101900-7Q7BG7HFE9Le9HDKz-hZ-Rlojqz-.jar.
Read timed out
Unable to read repository at http://eclipse.saplabs.bg//releases/helios/201102250900/aggregate/features/org.eclipse.jst.web_ui.feature_3.2.3.v201101262333-7F77FJ_C25TkfyypjhqQuxNYsMrJ.jar.
Read timed out
Unable to read repository at http://download.eclipse.org/releases/helios/201102250900/aggregate/features/org.eclipse.wst.common.fproj_3.2.3.v201101121727-377AC8s73543C6H4A5H.jar.
Read timed out
Unable to read repository at http://download.eclipse.org/releases/helios/201102250900/aggregate/features/org.eclipse.wst.common_core.feature_3.2.3.v201011031800-7B7DFEsF7RZHOaLfS0KpNJ.jar.
Read timed out
Unable to read repository at http://download.eclipse.org/releases/helios/201102250900/aggregate/features/org.eclipse.wst.common_ui.feature_3.2.3.v201011031800-7C78FPlEdhO_oXWe4k_elbMgT1Lq.jar.
Read timed out
Unable to read repository at http://download.eclipse.org/releases/helios/201102250900/aggregate/features/org.eclipse.wst.jsdt.feature_1.2.3.v201102160540-7C78FGUF9JgLWNO2UCNqfa.jar.
Read timed out
Unable to read repository at http://download.eclipse.org/releases/helios/201102250900/aggregate/features/org.eclipse.wst.server_core.feature_3.2.3.v20101104-30F8X8s734D3A4C.jar.
Read timed out
Unable to read repository at http://download.eclipse.org/releases/helios/201102250900/aggregate/features/org.eclipse.wst.server_ui.feature_3.2.3.v20101104-7B4FBuAtJb1qEKLnCKHHHI347.jar.
Read timed out
Unable to read repository at http://download.eclipse.org/releases/helios/201102250900/aggregate/features/org.eclipse.wst.web_core.feature_3.2.3.v201102160541-7E7AFI3AJrn5TN32vSJ8nRIWLD7_.jar.
Read timed out
Unable to read repository at http://download.eclipse.org/releases/helios/201102250900/aggregate/features/org.eclipse.wst.ws_core.feature_3.2.3.v201102160541-7L7RFf0FGtGd-nipy6nDoi4852.jar.
Read timed out
Unable to read repository at http://download.eclipse.org/releases/helios/201102250900/aggregate/features/org.eclipse.wst.ws_ui.feature_3.2.3.v201102160541-7I78FZIEtEoO2d7AsK6jSNqC-8jj.jar.
Read timed out
Unable to read repository at http://download.eclipse.org/releases/helios/201102250900/aggregate/features/org.eclipse.wst.xml_ui.feature_3.2.3.v201102160550-7H7AFUWDxumQJOi9ghcTb5YgkwEZ.jar.
Read timed out