Virtual box error. Fails to clone the virtual machine

Hi,
I am unable to use Virtual Machine properly and the error says that‘ Failed to clone the virtual machine’. Is this problem with a server? I have tried to start it manually but could not fix the problem. VM’s are on DRBD. What’s wrong? I need help.
Thanks.

Failed to done the virtual machine RSD_Centros5_5_x86_64_A
Cannot register the image C: program filesoraclevirtualboxvboxGuestAdditions.iso with UUID {0bda623d-b3cd-4e9a-b639-6acd8a611456} because a cd/dvd image C:program filesoraclevirtualboxvboxguestadditions.iso with UUID {0bda623d-b3cd-4e9a-b639-6acd8a611456} already exists
Details
Result Code: VBOX_E_INVALID_OBJECT_STATE (0x80BB00007)
Component: VirtualBox
Interface: IVirtualBox {c28be65f-43b4-81f1-eb60cb516e66}
