I am trying to install Eclipse plugin for Android Development.

Steps :

"Help" -> "Install New Software" Added "http://dl.google.com/eclipse/plugin/3.7" 
And then checked "Google Plugin for Eclipse" to install it.
The Installation moves upto 40% and I get this error everytime.

An error occurred while collecting items to be installed
session context was:(profile=PlatformProfile, phase=org.eclipse.equinox.internal.p2.engine.phases.Collect, operand=, action=).
Unable to read repository at <http://dl.google.com/eclipse/plugin/core/3.7/plugins/com.google.appengine.eclipse.core_3.0.1.v201206290132-rel-r37.jar>.
Connection reset

Needed Help to install ADT plugin for Eclipse for Android Developement.