Missing requirement error before installing ADT plugin for Eclipse 3.7.0 in Win 7

I am receiving the following error when trying to install the Android Development Tools section of the ADT Plugin:

Cannot complete the install because one or more required items could not be found. Software being installed: Android Development Tools 12.0.0.v201106281929-138431 (com.android.ide.eclipse.adt.feature.group 12.0.0.v201106281929-138431)

I have attempted to install the tools using Eclipse's Installer as outlined in the instructions on Developer.Android.org's getting started site (http://developer.android.com/sdk/eclipse-adt.html#installing). The other three components (Android DDMS, Android Hierarchy Viewer, Android Traceview) install fine.

I've attempted a local install to no avail. I have attempted installing different versions of Eclipse (3.6.2 and 3.5). 3.6.2 gave the same error. I was unable to run 3.5 as it did could not find my JDK installation. I have uninstalled and installed the Android SDK several times in different locations in case it was a permissions error.

Here are my version specs:

Windows 7, x64

Eclipse SDK

• Version: 3.7.0
• Build id: I20110613-1736
• Installed to: C:\Program Files\eclipse

Android SDK

• Installed From: installer_r12-windows
• Revision 12
• Installed to: C:\Program Files (x86)\Android

JDK Installed

• java version "1.7.0"
• Java(TM) SE Runtime Environment (build 1.7.0-b147)
• Java HotSpot(TM) 64-Bit Server VM (build 21.0-b17, mixed mode)
• Installed to: C:\Program Files\Java

I have Ubuntu 11.10 install, which has Eclipse 3.7.0 included.

I was having the same problem. I sorted it by:

Select Windows menu, then Preferences. Expand Install/Update and select Available Software Sites Ensure that everything in there is selected. By default only the Android site was selected for me.

Then try the Android ADT install again, ensuring that 'Contact all update sites...' is selected.

During the install, Eclipse can now find and install the required dependencies and everything will install and run just fine.

I don't think Java 7 is supported. Try with the latest Java 6.

Ensure you have the option "Contact all update sites during install to find required software". This option is located in the lower left corner on the first screen after choosing Help/Add New Software. This is unchecked by default. This WILL FIX the issue.