Tips and Tricks : Increase VirtualBox VDI disk size

Run this command >> VBoxManage modifyhd YOUR_HARD_DISK.vdi --resize SIZE_IN_MB

In example :-

To modify the existing vdi operating system to 40000MB instead of default 10GB.
Assume my file name is WinXP.vdi.

Command to run >>
VBoxManage modifyhd WinXP.vdi --resize 40000