Exchange 2007 to Exchange 2010 - unable to remove Public Folder Database

Hi

I made a transition from Exchange 2007 to Exchange 2010. All public foler have been replicated to Exchange 2010.
On the Exchange 2010 I also run moveallreplicas.ps1. Now one week later I tried to remove the public folder database, but I'm not able to do it: "The public folder database contains folder replicas."

If I do a get-publicfolderstatistics on the Exchange 2007 server I receive 3 public folders. But if I do a get-publicfolder with the identity I received from get-publicfolderstatistics, I receive the error "There is no existing PublicFolder that matches the following Identity: ....."

How can I remove these public folders?
Can I remove the Database using adsiedit?

Regards
Peter