Folders in search patch which are not shown in 'File Preferences'

yns's icon

I have 3 folders in my search patch which you can see when you open the textile by clicking on 'List Paths' in the 'File Preferences' window. But they are not selected in my userpaths nor are they subfolders of my userpaths.

I would like to delete them form my search path but I can't find a way. Suggestions?