Going nuts - can't delete artwork!

I have tried get info, making a new library and pasting a different artwork. None of this works.

The only thing that DOES work is if I copy the file to my local drive, then add to a iTunes library then delete. Otherwise every time I delete the artwork it instantly reappears!

Totally frustrated, as I don't want to rebuild and copy my library again! It would require copying to my external hard drive, moving them out of the folders to be sure then copying back again. This would take me about a week!

Help!

EDIT>

Created a new share and copied files from an external hdd then added to iTunes and I still can't delete the artwork! Looks like the permissions are buggered up on my external drive?

Right, I formatted the drive. I reinstalled Mavericks and still the problem persists! What the hell is wrong?

New iTunes Profile
Clean format NAS
Clean format Mavericks.

Yet I still cannot change the artwork! It keeps resetting itself as soon as I paste it in?

mic j said:

Could it be that you are using an OS that hasn't been released yet and has a few issues?

Click to expand...

It could of course, but why would it work then stop working even after a clean install? I am of course clean installing Mountain Lion, but after that I am out of ideas.

But seriously, why post something like that? It does not help in any way!

blueroom said:

It's helpful because beta software usually has a few bugs and omissions. It's also the most likely culprit.

Click to expand...

It seems that Mavericks was indeed the issue. I just tried with OSX Mountain Lion and all is well.