get "Guest Additions" from: http://download.virtualbox.org/virtualbox/

Installing Guest Additions on Ubuntu

Follow these steps to install the Guest Additions on your Ubuntu virtual machine:
 1. Login as ubuntu;
 2. Click on Applications/System/Terminal (or on Applications/Terminal, if you are using the 6.06.1 Dapper Drake release);
 3. Update your APT database with sudo apt-get update, and typing your password, if requested;
 4. Install the latest security updates with sudo apt-get upgrade;
 5. Install required packages with sudo apt-get install build-essential module-assistant;
 6. Configure your system for building kernel modules by running sudo m-a prepare;
 7. Click on Install Guest Additions… from the Devices menu, then choose to browse the content of the CD when requested.
 8. Run sudo sh /media/cdrom/VBoxLinuxAdditions.run, and follow the instructions on screen.

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!!! For GuestAdditions fully working (USB 2) a group vboxusers is needed both on host and on virtual machine
!!! and access for eg. Jim !


Also possible:
1. open vbox
2. virtuelle Maschine auswählen (z.B. "win7 prof 64 r700")
3. Klicke: Ändern / Massenspeicher / Controller IDE / sekundärer Master
4. Klicke CD-Symbol, wähle Pfad zu VboxGuestAdditions.iso (korrekte version beachten!)