If you have recently updated your PC to Windows 10 you might have noticed that our beloved Xamarin Android Player does not work anymore. Whenever we try to start it, the error message “Could not configure host-only network. Please reboot the computer and try again.” appears.This problem is caused by compatibility problems that VirtualBox 4 seems to have with Microsofts latest operation system.To fix this,we need to reinstall the Xamarin Android Player and configure the Virtual Box properly.

Step 1
Uninstall the Xamarin Android Player and VirtualBox completely. Make sure that there is no XamarinAndPlayer directory underC:\Users\{YOUR_USERNAME}\AppData\Roaming left. If there is one, delete it.

Step 2
Download the Xamarin Android Player and install it. But do not start it yet! We need to do some other work first!

Step 3
Download and install the latest version of VisualBox. It should be version 5 at least. This will update and clean the version that comes with Android Player at the moment to a version that is more compatible with Windows 10.

Step 4
Now we need to configure the fresh installation of VirtualBox. For this, start it and go to the File/Preferences/Networking page and select the Virtual Host Only tab.Klick on the edit icon for the one existing network adapter and make sure the it is set in the following way:

<code class="language-markup">Adapter:
IPv4 Address: 10.71.34.1
IPv4 Network Mask: 255.255.255.0

DHCP Server:
Enabled
Server Address: 10.71.34.2
Server Mask: 255.255.255.0
Lower Address Bound: 10.71.34.101
Upper Address Bound: 10.71.34.199```

Save your changes and close VirtualBox. Now we can launch the Xamarin Android Player and start installing the virtual machines available for download. It will find the correctly configured host only network adapter now.

I really hope that helps everybody who is frustrated after updating his system to Windows 10. Huge thanks to [Danny Pronk from the Xamarin Forums](https://forums.xamarin.com/discussion/comment/139102/#Comment_139102) who found that solution.