virtualbox.org

have copied the vdi file from existing ubuntu 8.04 running vbox to newly setting ubuntu 9.04 with vbox 2.2.2. the vdi file has been attached. the boot starts but hangs at mup.sys in safe mode.

any solutions?

Check type of ide controller. Now standard is piix4 previously piix3.
Also make sure settings for acpi ioapic et.al. is the same.