I\'m developing for Android with Eclipse, and all was working well until yesterday. I used Ninite to update all my stuff, including JREs and everything (pro tip: do not do t
I found the answer to the problem. (I'm using Helios, but it should work anyway)
Goto folder /Program Files(x86)/Eclipse/Plugins/ and make sure previous older versions of com.android.ide.eclipse.adt.package_##... are deleted (sometimes update fails to delete because of UAC). Keep the current desired version and complete the following.
Run Eclipse as administrator or disable UAC temporarily. (windows 7)
Go to Help → Install New Software.
On Work with: type https://dl-ssl.google.com/android/eclipse/ and press ENTER.
Wait for Eclipse to fetch the repository. An item named Developer tools will appear in the list.
Mark it for install, press Next and follow the steps to install the ADT tools.
When finished, it will ask to restart Eclipse. Make sure you do this.
When Eclipse restarts, all your Android SDK packages should show up again.
Dont forget to resume UAC if you need it.