How to mount USB to your Windows Sandbox

 It is not possible to mount flash disc directly to the sandbox instance, but you can use following hack:

Create a file named sandbox.wsb

Put following text inside:

<Configuration>

<VGpu>Default</VGpu>

<Networking>Disable</Networking>

<MappedFolders>

<MappedFolder>

<HostFolder>D:\Public</HostFolder>

<ReadOnly>false</ReadOnly>

</MappedFolder>

</MappedFolders>

<LogonCommand>

<Command>explorer.exe C:\users\WDAGUtilityAccount\Desktop</Command>

</LogonCommand>

</Configuration> 

Then just doubleclick this file and Sandbox with attached USB is here ;)