Error -42408 on launch!

Hi All!

I'm on Mountain Lion, and I have updated iTunes to version 11, didn't like it, and decided to go back. Now I'm getting an "Error -42408" on each launch, while the app and Store both work fine.

After doing about an hour of digging, it looks like iTunes gives a -42408 when its having problems talking to the iTunes Store.

So far, I have tried:

-Removing iTunes.app from the Applications folder and reinstalling.

-Removing /Library/iTunes folder

-Removing ~/Library/iTunes folder

-Removing iTunes preference files in ~/Library/Preferences and /Library/Preferences

-Removing traces of installing v.11, by:

>Changing InstallHistory.plist in /Library/Reciepts

>Removing iTunes PLIST and BOM files from /private/var/db/receipts/

-Removing /Users/Shared/SC Info folder

-Using AppZapper to see if I could have missed something

...but the error persists.

As far as I can tell, there are two possibilities:

1. Some file that iTunes accesses on launch is telling iTunes something it doesn't like. (like an incorrect version number), or

2. Some file that iTunes accesses on launch is telling iTunes what to tell the iTunes Store, and the Store doesn't like what this file has to say.

Any ideas? I'm stumped! 😟