Is your internet connection working fine?? In the setup window there is an option on the "Settings" screen which says "Force https:// sources to be fetched using http://" check it and then press "Save & Apply", that should do the trick...
when i accessed this url through browser i got a page full of some information, i am pasting a part of it here
Google APIs 3 Google Inc. 03 Android + Google APIs http://developer.android.com/ 34908058 1f92abf3a76be66ae8032257fc7620acbd2b2e3a google_apis-3-r03.zip com.google.android.maps API for Google Maps. 1.1 2 1 Android SDK Platform 1.1_r1 http://developer.android.com/sdk/android-1.1.html 46828615 a4060f29ed39fc929c302836d488998c53c3002e android-1.1_r1-windows.zip 45584305 e21dbcff45b7356657449ebb3c7e941be2bb5ebe android-1.1_r1-macosx.zip 45476658 c054d25c9b4c6251fa49c2f9c54336998679d3fe android-1.1_r1-linux.zip 1.5 3 03 Android SDK Platform 1.5_r3 http://developer.android.com/sdk/android-1.5.html 54489489 d3cf755695ed7f104d768b3ae9a748ceca5f6c69 android-1.5_r03-windows.zip 53224899 c89f8f85d15ac467c624b05af2237063a69a1633 android-1.5_r03-mac_x86.zip 53137673 e6370835102dd624b49207162a0be02cd3f90091 android-1.5_r03-linux_x86.zip This is the Android Software Development Kit License Agreement. 1. Introduction 1.1 The Android Software Development Kit (referred to in this License Agreement as the "SDK" and specifically including the Android system files, packaged APIs, and Google APIs add-ons) is licensed to you subject to the terms of this License Agreement. This License Agreement forms a legally binding contract between you and Google in relation to your use of the SDK. 1.2 "Google" means Google Inc., a Delaware corporation with principal place of business at 1600 Amphitheatre Parkway, Mountain View, CA 94043, United States. 2. Accepting this License Agreement 2.1 In order to use the SDK, you must first agree to this License Agreement. You may not use the SDK if you do not accept this License Agreement. 2.2 You can accept this License Agreement by: (A) clicking to accept or agree to this License Agreement, where this option is made available to you; or (B) by actually using the SDK. In this case, you agree that use of the SDK constitutes acceptance of the Licensing Agreement from that point onwards. 2.3 You may not use the SDK and may not accept the Licensing Agreement if you are a person barred from receiving the SDK under the laws of the United States or other countries including the country in which you are resident or from which you use the SDK. 2.4 If you are agreeing to be bound by this License Agreement on behalf of your employer or other entity, you represent and warrant that you have full legal authority to bind your employer or such entity to this License Agreement. If you do
I was also having the same error when I came across this thread.
Thanks to Bilal, I looked into the xml file & found out :
Now manually downloading this after appending it in http://dl-ssl.google.com/android/repository url.
Hopefully, it should work fine within the platforms folder.