Setting up rights between Ubuntu/Samba in Virtualbox and OS X as a host
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I have a virtual Ubuntu server running in VirtualBox under OSX, everything is setup by default, I didn't tweak anything special.

I added Samba in Ubuntu and created a user to connect with from my OSX (=> the host), until here everything's ok. 

When I connect to the server, OSX displays the normal dialog box asking me wether I want to connect as a Guest or a known user. Whatever I use, it works and connects to the server, and I can then see my shared /var/www folder of my Ubuntu installation.

The weird thing happens when I try to create or modify a file or folder inside /var/www from OSX in Finder.

First it displays the OSX system authentication box, the usual one. I enter my Mac username & password => OK, but then it shows an error saying I don't have enough rights to modify the file or folder.

The /var/www belongs to root:root by default and the user I connect with is also in the root group.

Is there anything special to do to be able to modify files & folders ?

Thanks in advance.    
 