Resize a VirtualBox guest Linux VDI Disk under Windows Host

Resize VirtualBox Ubuntu

1. Shut down VirtualBox.
2. Make a copy of the VDI file – just in case (“MyLinux.vdi” -> “MyLinuxCopy.vdi“)
3. Go into the Windows command prompt (Start->type “cmd” into the box)
4. cd to the location of the VDI file that you wish to resize, e.g., “d:\MyLinux.vdi“
5. At the Windows command prompt, type:
   D:\>VBoxmanage modifyhd MyLinux.vdi --resize 100000
   this will re-size the drive to 100 GB. Pick a value that suits you. Note, your vdi file will not change in size at this point. 
   The output should look like:
 D:\>VBoxmanage modifyhd MyLinux.vdi --resize 100000
 0%...10%...20%...30%...40%...50%...60%...70%...80%...90%...100%

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1. Switch on Ubuntu.
2. Open GParted.
3. Right click on Disk and resize