I have tried to update my Eclipse. Currently I have till 2.2 Android SDK in my Eclipse. Yesterday I have updated my Eclipse like this:
Eclipse -> window -> Android S
You have updated the android sdk but not updated the adt to match with it.
You can update the adt from here
You might need to update the software source for your adt update
Go to eclipse > help > Check for updates.
It should list the latest update of adt. If it is not working try the same *Go to eclipse > help > Install new software * but now please do the follwing:
Click on add
Add this url : https://dl-ssl.google.com/android/eclipse/
Give it any name.
It will list the updates available- which should ideally be adt 20.xx
Eclipse will restart and hopefully everything should work fine for you.