There might not be malicious software in Spotify, but this is malware-like behaviour. A program going against the settings as specified by the user, and strapping itself into the boot-sequence regardless of user preference... The Spotify developers either do not know how, or don't care enough, to fix this. Don't blame malevolence when ignorance or apathy are more likely explanations. The simplest fix I found it to simply rename the "Spotify.exe" and "SpotifyLauncher.exe" to "Spotify1.exe" and "SpotifyLauncher1.exe". You can find them in "C:\Users\YourUsername\AppData\Roaming\Spotify\" Then it is simply a matter of making a shortcut to the renamed Spotify1.exe in order to launch the program when you want to, rather than having it start with the computer. The problem is of course that with every Spotify update you will have to re-do this if you want to prevent it starting with boot.
This is actually fairly easy. Open Spotify, click the Edit menu, and select Preferences. Scroll all the way to the bottom, and select the option labeled "Don't open automatically." That should do it - all you need to do at that point is close Spotify, and optionally restart your computer to test the new settings.
In my preferences "Don't open automatically" is always checked, spotify still starts automatically every time I turn on my computer. What do I do to stop it from doing this? Allready tried uninstalling and re-installing the program, with no luck.
My settings is to not automatically start and I used Revo to remove it from the autostart lists and started my machine this morning and what do you know; Spotify is starting with my machine. . . It's starting to act like mal-ware. Seriously, I might remove it and not come back if this isn't fixed.
Went through all the "easy" fixes, disabled it from starting automatically in msconfig and ccleaner, which works for exactly one time restarting my computer. Then it pops right back up.
I'm really quite surprised that Spotify seems to have no real answer to this issue whenever it comes up on this community board. By all accounts Spotify is a reputable company, and I can't imagine an unecessary annoyance like this would be good for their business.
Weird. After changing this setting, I've not had it auto-start on my personal machine... It could be that somehow, there are two versions of Spotify on your computer. I'd recommend trying a clean installation of Spotify, and trying setting again.
Screen shot of msconfig after Spotify has been disabled from starting automatically and system has been restarted. Note that the 2 Spotify items on top have appeared as enabled, while 2 duplicates on the bottom remain disabled. After the next restart, Spotify will open automatically regardless of the settings in Spotify preferences.
(I am using Windows 7, 64-bit, service pack 1, and Spotify version 0.8.3.222.G317ab79d)
EDIT: Itunes, it appears, has the same problem, but it at least doesn't take over my monitor at startup. : /