I have install VirtualBox on Ubuntu LTS 22 Server and I have attached a 2TB SATA disk for holding several Virtualbox VMs.

 

When I tried to point VM to be created in that larger partition mounted as /u01, I got following error:

 

Please check that the parent really exists and that you have permissions to create the machine folder.

 

You can usually resolve this by updating the Default Machine Folder in the VirtualBox settings. Open the settings by going to the File -> Preferences menu.