When trying to upgrade Android SDK Tools to revision 16, I am getting the following error:
Failed to rename directory C:\\android-sdk-windows\\tools t
I ran into the same problem.
Most probably, you have a project opened in Eclipse (or android studio), and this project uses files that the SDK manager is trying to access or update.
So, the project is reading from some SDK platform folders/files, and the SDK manager is trying to overwrite it at the same time (for updating).
This is why you do not have permissions, not because you are not administrator.
Try closing Eclipse, click 'YES' in the SDK manager warning message (or re-run SDK manager again while Eclipse is not running).