There have been virtual machine images made available for IE testing around for a while now, they’re awesome and we love them. But there is one tiny annoyance about using them, the 30 days trials eventually expire and you have to stop what you’re doing to restore a snapshot or set up the machine again.
Luckily VirtualBox has a little known feature called immutable disks that makes this problem go away. When a virtual hard disk image is marked as immutable and changes made to it are reset each time the machine boots, effectively as if the snapshots were restored each time it boots. Set the disk up before the first ever boot and you get an infinite testing machine.
It’s pretty easy to set up but there are two things to be aware of; you need to make the disk immutable before you first boot up the machine and the disk has to be unlinked from the machine before it can be modified.
Once the machine has been imported open the storage settings and remove the main hard disk image from it using the little minus icon at the bottom of this screen.
Once the disk has been removed open up the virtual media manager from the file menu of the main manager. Find the disk for the newly created machine and select modify from its right click menu. In this menu the mode can be set to immutable, for the curious there is a description of the other modes on the VirtualBox website.
Back in the storage settings click the little plus icon next to the controller to reattach the disk to the machine. Make sure it’s done in the same way as it was to start with or Windows may get annoyed.
Start up the machine to make sure it boots. An easy test of the resetting is to create a new file on the desktop (or anywhere) then reboot the machine and make sure it’s not there any more.
You now have an IE testing machine that will reset it’s licence each time it starts up! The only disadvantages being that you can’t install new software and the browser history gets reset each time. Also something to note also is that the machine has to actually power off to be reset, rebooting from Windows does nothing.