get rid of iCloud nag in iTunes

[rjcchan]

Upgraded iTunes to 12.3. Every time I open it I get a nag that my iCloud session has timed out. As far as I know I never had a session and don't want one. How do I turn this nag off?

 

[Partron22]

I start up iTunes with a script that auto-dismisses warning dialogs:

--iTunesSU
-- This is just PlayPause Script saved in App form
-- So I can give it an Icon and Drag it into the Dock
-- BP July 2015

set isrunning to 0
tell application "iTunes"
    if it is running then
        set isrunning to 1
        playpause
    end if
end tell
if isrunning is equal to 1 then return
-- It's not running, want to start it up, and kill any warning dialog
tell application "iTunes"
    activate -- this'll start iTunes if it's not already up
    --    try
    --        set frontmost to true
    --    end try
end tell
delay 0.2 -- iTunes needs a little time to stabilize
tell application "System Events"
    try
        set z to name of front window of application process "iTunes"
        -- This returns "" if it's a warning dialog
        -- "iTunes" if it's the main music window or mini player
        -- Track and album name if it's cover view up front
        -- error if no iTunes windows are open
        -- "General Preferences" if Prefs is open
        -- Album name if "Get info" is open
        -- "Equalizer" if equalizer window is open
    on error
        set z to "Bubblepuppy"
    end try
    if z is equal to "" then
        --set z to name of (static text of window 1 of application process "iTunes") as text -- might eventually be useful
        delay 0.2 -- iTunes needs a little time to stabilize
        keystroke "
"
    end if
end tell
-- iTunes doesn't remember what's playing between starts, so the following lines will just start playing whatever happens to come up first
-- always the same, or shuffled if shuffle is set.
--delay 0.1
--tell application "iTunes" to playpause
return

I'm using iTunes 10.4.1 so the code may need a little tweaking for your purpose.
When you get it working as you like, save it as an App, give the App a nice custom Icon, and drag it into the dock. Pull your old iTunes icon out of the dock.