Q:

How can I access shared folders on an Ubuntu host and a Windows XP guest?

I have installed VirtualBox 4.1.18 on Ubuntu 12.10 and I'm hosting Windows XP.
I want to share a folder between Ubuntu and Windows XP.
I have installed guest additions on the guest machine, but when I'm trying to access the shared folder, I can't find them anywhere.
So, where can I access those shared folders?

A:

At least for Ubuntu 15.04 host system and Windows Server 2012 R2 and VirtualBox 4.3.32_Ubuntu r104062, the following works. I assume, it works the same way with other versions of Windows as guest:

Boot the Guest operating system in VirtualBox.  
Select Devices > Shared Folders in the VirtualBox menu
Choose the Add button. Select the host folder you want to share
Select Auto Mount
Reboot your guest system
Now you will find your shared folder mapped as network drive on Windows. No need to fiddle around with manually booting something on Linux or Windows command line as described in this guide.

A:

Have you read this guide:
Shared folders
The process of creating a shared folder is well explainded in this guide.
In short:
1) In your VM properties set a shared folder on host machine.
2) Boot the guest machine and run the following command:
net use x: \\vboxsvr\share

where x - is the name of the drive with virtual folded. You may leave it as is, and share - is the name of the folder you've created on host machine.

