I recently had to start using Windows to connect to a client’s VPN network. Their VPN solution only works (or is supported) on Windows, plus the need to test a few things on Internet Explorer :(

Previously I had used Amazon EC2 whenever I needed to use windows, to avoid license costs, 20GB of my drive wasted and the CPU/RAM overhead, but this time there was no way out, didn’t seem cool to store the VPN credentials on a public cloud instance, although it’s probably as safe. So I bought Windows 7 online and downloaded the 3GB iso image and VMWare Fusion for OS X which happens to have a 30-day trial. Got Win 7 working there with no problems, which is not what I can say about the VPN setup.

Then I got good recommendations to try VirtualBox, which is both open source and free as in beer, and was glad to see there are ways to easily move your VMWare images to VirtualBox.

Step by step instructions

To move the Windows 7 image to VirtualBox 4.1 just needed to

1. Uninstall the VMWare tools and shutdown windows
2. Copy the disk files from VMWare image to a new folder
1. In Documents/Virtual Machines right click on the image, Show package contents
2. Copy all *.vmdk files to a new folder
3. Create a new VirtualBox machine with the same characteristics
1. Make sure you choose Windows 7 64 bits if that’s what you used
2. On Virtual Hard Disk, choose the main vmdk file you copied in previous step (although you’ll need to change the default storage config later)
3. Customize created VM settings:
1. General: Windows 7 64 bits
2. System/Motherboard: set the same amount of base memory as the VMWare one
3. System/Motherboard: Enable IO APIC
4. Storage: By default VirtualBox adds it to SATA controller but you have to remove the SATA controller, and use IDE PIIX4 without host I/O cache, attaching vmdk to primary master IDE, leave CD/DVD drive
4. Boot the VirtualBox VM and follow any prompt to restart Windows to install new devices
5. On the VirtualBox Devices menu, click on install guest additions

Troubleshooting

Several things went wrong before I got it working, so just in case you have the same problems

• Stuck in “Windows is loading files” black screen, rebooting continuously: make sure you have selected 64 bits Windows and enabled IO APIC
• Blue screen of death: Remove SATA, SCSI and any other non-IDE controllers from Storage, attach vmdk to IDE and make sure PIIX4 is selected
• Windows needs to be repaired / Cannot repair windows: same as previous one, make sure disk is attached to IDE