Public Folder appears in address book but not in PFMC

Hi,
when I've a look in the Public Folders addressbook I see a PF _Test, but when I look for this PF in the managment console I can't find. The PS command "get-publicFolder -recurse -resultsize unlimited | where {$_.name –like "_T*"} | fl" print no result on the screen. In ADCU domain\Microsoft Exchange System Objects I also see this PF.

Any suggestion how I can solve this?

Thx, Reinhard