How to Read Spotify Inbox Messages
When you have Spotify running and see a number next to the Spotify icon in the Start bar in Windows 7 or your Dock on the Mac, it means that you have that number of new items waiting in your Inbox. This number also appears next to Inbox in Spotify’s left sidebar.
Click Inbox in the left sidebar to view these items, as well as who sent them. Each unplayed item is shown in bold white to make it stand out and has a blue dot next to the item name. If the item is a track, double-click it to start playing it right away, and the track becomes unbold.
Double-click an album or playlist to go to its track listing, or double-click an artist to go to his artist page. From there, you can play the individual tracks, if you want.
If the person who sent you the item has left you a message, you see a small speech bubble appear next to her name. Click this speech bubble to read the message, which appears in a little pop-up window.
You can’t really reply to tracks in the traditional sense to say thanks, but why not send the user a thank you track as a reply, with your own message?
By the way, tracks play on your computer only if they’re already in Spotify’s streaming database or stored locally — otherwise, they appear grayed-out and are unplayable.