I had the same issue, spotify prefs, registry keys, msconfig, startup folder, and 3rd party boot utilities (ccleaner, glary utilities) would not work, or was not able locate the Spotify startup files. Here are the steps if all else seems to not work.
First open Spotify if it is not already running.
(1) Delete the Spotify Icon on your desktop if you currently have one. (Any Spotify shortcuts created before completing these steps will no longer work).
(2) Open task manager (ctrl + shift + esc)
(3) Switch to Processes tab and Right-Click "Spotify.exe" and select "open file location".
(4) In this folder you should see two application files named, "Spotify" and "SpotifyLauncher".
Right click each file and add a 1 to the end of the file name.
"Spotify1" and "SpotifyLauncher1"
(5) Right click Spotify1 and select create shortcut. It should make a shortcut icon which you can drag to your desktop. (This file can be renamed to anything as long as the target is not changed).
Once this is complete, it should no longer load on startup. You can now use the created desktop shortcut to open Spotify.
Hope this helps - IS
I just installed (06/19/2017) Spotify so should have newest version.
click on down arrow its to the right of profile button in upper right of page.
click on settings. Scroll down to end of settings then click on "advanced settings"
Scroll down to "Startup and Window Behaviour" Subhead says "Open Spotify automatically.
Down arrow gives three choices. Choose "NO". Restart.. Spotify should not start.
And shortcut on desktop put there on installation should now work
In nowadays, Spotify opens on startup, i disabled this option but it still opens.
I removed from msconfig, but it appeared in msconfig again.
Please fix this
I had this problem and changing the settings and restarting didn't work. Go to task manager<startup<spotify and select disable then restart. That worked for me.
I solved this by disabling Open Spotify after you log into your computer (set to No) AND Allow Spotify to be opened from the web under Preferences... > Advanced Settings.
If you don't disable the second one, the process called SpotifyWebHelper.exe is launched at startup and for some reason it decides it's time to launch Spotify too.
Yes this will prevent you from opening Spotify links (you can still see them in your browser) but I guess this will be sorted out at some point.