you MUST run eclipse as an administrator to install plugins for Vista or 7 !!! right-click the eclipse.exe file (not the shortcut). If you still have problems, try the next step.
one reason this could happen is because you first need to enable a release compatible with your version of eclipse:
http://download.eclipse.org/releases/juno (or helios, ganimede, indigo, etc.)
if you are missing a sroid sroid, download from http://developer.android.com/sdk/index.html
after installing it, you must go to the folder c: / Program Files (x86) / Android / android-sdk / platform / and create a new (empty) folder "android-7". then create a folder called temp in c: / Program Files (x86) / Android / android-sdk / and you will be asked to download the SDK when you run eclipse again (always as administrator)
finally restart and you should be fine
PS: you have to update your eclipse (under HELP) and then exit it. restart in administrator mode and open the Android SDKs (not HELP, tab on the left [not on my workstation right now, later will be]).
without installation, basically everything is there (from 3 to 12 hours, depending on the speed of your connection), you will not have a complete environment, and some compilations simply will not work.
tony gil
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