Mac Solution: A Firewall may be blocking Spotify Error code auth:3

[iNick1]

Open Finder 

In the Menu Bar select Go and then 'Go to Folder' 

Enter: /private/etc/hosts

Locate the file called 'host' and drag to desktop 

Open the file and replace the text with: 

##
# Host Database
#
# localhost is used to configure the loopback interface
# when the system is booting. Do not change this entry.
##
127.0.0.1 localhost
255.255.255.255 broadcasthost
::1 localhost

Save the file

Copy this back into the /private/etc/hosts location and select 'replace' when the conformation shows. 

Restart/Reinstall Spotify 

[garyjofre]

Me sirvió ... muchisimas gracias.

[Cloud1]

But my hosts file already had that in it!