title: Installing Xamarin fail on Mac due to Android SDK
body: <p>I'm trying to install Xamarin on my MacBook Pro 2011 running 10.7.4.
  When I run the installer it attempts to install the Android SDK first, however after a while it fails and the error report states:</p>
  
  <pre><code>Error downloading from Google server. Android SDK.
  The operation has timed out.
  Exception type: System.Net.WebException
  Message: The operation has timed out.
  at System.Net.WebConnectionStream.Read (System.Byte[] buffer, Int32 offset, Int32 size) [0x00000] in &lt;filename unknown&gt;:0
  at Xamarin.Web.Installer.DownloadService.DoDownload (Int64 totalBytes, System.IO.Stream responseStream, System.IO.Stream outputStream, System.Object state) [0x00000] in &lt;filename unknown&gt;:0
  at Xamarin.Web.Installer.Utilities.DownloadUrl (System.Net.HttpWebResponse response, System.String url, System.Action`4 doDownload, Boolean noCache, System.Object state) [0x00000] in &lt;filename unknown&gt;:0
  
  Android SDK installation failed with more than one exception (Attempt #Android SDK)
  Some installation errors are present.
  Exception type: System.AggregateException
  Message: Some installation errors are present.
  Exception type: Xamarin.Web.Installer.InstallException
  Message: Download failed.
  at Xamarin.Web.Installer.Installer.BaseSoftwareItem.ValidateDownloadItem () [0x00000] in &lt;filename unknown&gt;:0
  at Xamarin.Web.Installer.Installer.AndroidSoftwareItem.Install (UInt32 tryNumber) [0x00000] in &lt;filename unknown&gt;:0
  at MacInstaller.WizardPageInstallationController.InstallationWorker () [0x00000] in &lt;filename unknown&gt;:0
  Exception type: System.Net.WebException
  Message: The operation has timed out.
  at System.Net.WebConnectionStream.Read (System.Byte[] buffer, Int32 offset, Int32 size) [0x00000] in &lt;filename unknown&gt;:0
  at Xamarin.Web.Installer.DownloadService.DoDownload (Int64 totalBytes, System.IO.Stream responseStream, System.IO.Stream outputStream, System.Object state) [0x00000] in &lt;filename unknown&gt;:0
  at Xamarin.Web.Installer.Utilities.DownloadUrl (System.Net.HttpWebResponse response, System.String url, System.Action`4 doDownload, Boolean noCache, System.Object state) [0x00000] in &lt;filename unknown&gt;:0
  Exception type: Xamarin.Web.Installer.InstallException
  Message: Download failed.
  at Xamarin.Web.Installer.Installer.BaseSoftwareItem.ValidateDownloadItem () [0x00000] in &lt;filename unknown&gt;:0
  at Xamarin.Web.Installer.Installer.AndroidSoftwareItem.Install (UInt32 tryNumber) [0x00000] in &lt;filename unknown&gt;:0
  at MacInstaller.WizardPageInstallationController.InstallationWorker () [0x00000] in &lt;filename unknown&gt;:0
  Exception type: System.Net.WebException
  Message: The operation has timed out.
  at System.Net.WebConnectionStream.Read (System.Byte[] buffer, Int32 offset, Int32 size) [0x00000] in &lt;filename unknown&gt;:0
  at Xamarin.Web.Installer.DownloadService.DoDownload (Int64 totalBytes, System.IO.Stream responseStream, System.IO.Stream outputStream, System.Object state) [0x00000] in &lt;filename unknown&gt;:0
  at Xamarin.Web.Installer.Utilities.DownloadUrl (System.Net.HttpWebResponse response, System.String url, System.Action`4 doDownload, Boolean noCache, System.Object state) [0x00000] in &lt;filename unknown&gt;:0
  Exception type: Xamarin.Web.Installer.InstallException
  Message: Download failed.
  at Xamarin.Web.Installer.Installer.BaseSoftwareItem.ValidateDownloadItem () [0x00000] in &lt;filename unknown&gt;:0
  at Xamarin.Web.Installer.Installer.AndroidSoftwareItem.Install (UInt32 tryNumber) [0x00000] in &lt;filename unknown&gt;:0
  at MacInstaller.WizardPageInstallationController.InstallationWorker () [0x00000] in &lt;filename unknown&gt;:0
  Exception type: System.Net.WebException
  Message: The operation has timed out.
  at System.Net.WebConnectionStream.Read (System.Byte[] buffer, Int32 offset, Int32 size) [0x00000] in &lt;filename unknown&gt;:0
  at Xamarin.Web.Installer.DownloadService.DoDownload (Int64 totalBytes, System.IO.Stream responseStream, System.IO.Stream outputStream, System.Object state) [0x00000] in &lt;filename unknown&gt;:0
  at Xamarin.Web.Installer.Utilities.DownloadUrl (System.Net.HttpWebResponse response, System.String url, System.Action`4 doDownload, Boolean noCache, System.Object state) [0x00000] in &lt;filename unknown&gt;:0
  </code></pre>
  
  <p>What's wrong?</p>