https://stackoverflow.com/questions/36857343/virtualbox-import-error-cannot-register-the-dvd-image

Err-begin:
Konnte die virtuelle Maschine in /media/sdb2/Vbox1/! win7 prof 64 r700-Klon/! win7 prof 64 r700-Klon.vbox nicht öffnen.

Cannot register the DVD image '/usr/share/virtualbox/VBoxGuestAdditions-6.1.26.iso' {844243b8-a8ef-438b-a873-e704e081cab2} because a CD/DVD image '/usr/share/virtualbox/VBoxGuestAdditions-6.1.26.iso' with UUID {0f05aca7-147b-40f8-be3a-8d7df834196b} already exists.

Fehlercode: NS_ERROR_INVALID_ARG (0x80070057)
Komponente: VirtualBoxWrap
Interface: IVirtualBox {d0a0163f-e254-4e5b-a1f2-011cf991c38d}
Err-end


I solved it by open the file win 7 64.vbox with text editor and remove the tag:

<DVDImages>
   <Image uuid="{fd686a98-c1a6-42d9-82aa-67728b524d53}" location="C:/Program Files/Oracle/VirtualBox/VBoxGuestAdditions.iso"/>
</DVDImages>

Know that by removing the tag it will be added as empty tag. and reopent the vm of virtual box again. and it worked