Why does stereo mix not work on this computer?

[instCass]

I am trying to get Stereo Mix to work when playing music on pc in virtual setting.   

[WarrenGnv]

Solution to Stereo Mix,     go to control panel,  click on sound,  when the window opens  click on recording tab,  stereo mix should be one of the items listed,  right click on that  select enable,  then click apply ,  ok,  it should now work.