Hello
Many people have posted on the 'net, describing VirtualBox PUEL upgrade as straightforward. My experience of several upgrades was very different with quite some breakage, repair and grief
Here's the procedure I have evolved by experimentation to make it less painful, more routine. Several of the specifics (paths, virtual machine name WXP, Kaspersky, TweakUI, and my personal user name is c on ubuntu and C on WXP virtual) will be different on other systems but it should...