SDK Manager told me I had updates and updated me from version 21 to 22, then said I should check for updates. I\'m running bundled eclipse/ADT from about last month, Juno ve
I had a similar problem and spent hours trying the solutions above and those listed in https://code.google.com/p/android/issues/detail?id=60149. Nothing worked for me.
Finally, I reinstalled the eclipse plugin (Help->Install New Software-Add, and then use https://dl-ssl.google.com/android/eclipse/). This was simple and it worked. I think this was all due to a bug in eclipse that this new plugin version fixed.
(More details here: http://developer.android.com/sdk/installing/installing-adt.html)
Just change location address from http:// to https://
Go To Eclipse menu Window -> Preferences then Install/Update -> Available Software sites, select "Android Developer Tools Update Site" and click "Edit"