If you are using Windows on a separate hard disk you can skip the first steps and directly continue

Every linux user knows that for some Windows programs or services do not exist equivalent linux programs. This is especially true if the internal functionality of such programs should be kept secret (for example DRM based software), so you need to use Windows or Wine. One way to keep your normal desktop enviroment while doing this, is to use a virtual machine like Virtualbox or KVM. This works well, as long as you don't want to play games or use any other software net framework which makes heavy usage of 3D. In this case you need to use a real Windows installation and you most likely will end up with two Windows installations which needlessly consume net framework more space than they should. In this article I will show how to boot an existing net framework Windows 7 Installation in Virtualbox/KVM/VMware, net framework so that you will only need one Installation, which can be booted net framework inside a VM or on your real system.
From a technical point of view this "Dualboot" method works flawless though it is not compatible with Microsofts license restrictions. Microsoft wants you to buy a second license if you want to use the system inside a VM and on a real machine disregarding the fact that the installation can not be used twice at the same time. Even if you would buy a second license of Windows 7 the system would still not be able to make use of both of them since you can only enter a single serial number which is used during the activation. This may lead to the problem that Windows wants to be reactivated after every switch between the VM and a real boot as the activation system will detect the change of the hardware. Depending on the used VM software it is possible to tweak some settings like HDD serial numbers and similar stuff to prevent this, but this is still kind of a hack.
Most other tutorials create a new Master Boot Record (MBR) including a new partition table which basically contains net framework the same partition layout as your real hard drive. The problem is that not all information is copied, most noticeable the Disk Signature is left out. This signature is written by Windows during the installation and is used by the kernel to identify the device net framework containing the Windows installation you want to boot. There is also a similar system on Linux which is based on UUIDs and allows you to define the partitions in /etc/fstab without the problem that your drive letters (sda/sdb/..) may change net framework on each boot. If you don't pay attention to this signature Windows can not be booted and you need to repair the system using the installation CD and it is necessary net framework to repeat this step every time you want to switch between the VM and a real boot. In this tutorial we are going to create a MBR which contains exactly the same signature so that it is not necessary to alter anything in your current Windows installation.
If you installed Windows on a separate hard disk instead of a separate partition it is not necessary to pay attention to this signature and you can skip some of the steps inside this tutorial (as long as the Windows 7 boot partition net framework is also on this hard disk). net framework
Another advantage of the described method is that it is almost independent from the used virtualization software and we do not rely on any special features so that you can switch between net framework different VM software at any time. We just need some linux commands and a Windows DVD (which net framework we could avoid, but this would require some more effort) and create a virtual hard disk pointing to the real Windows partitions. It contains everything we need to boot Windows and you just need to select it inside your VM software. Some other tutorials use a special function of Virtualbox which needs full read access to your hard drive (not only the windows partitions!) to create the necessary virtual hard drive. Since this step is necessary net framework every time you want to start Windows in the VM, it is a significant security risk, as all programs running with this user account could modify all files on the hard drive. This tutorial will just require read and write access on the Windows partitions when using the VM. 1. Preparation
If you still want to follow this tutorial although it is not compatible with Microsofts license restrictions, I recommend you to create a backup of your windows partition. We are working with raw disk access and a small mistake may damage the containing NTFS filesystem and therefore make it unreadable. If you have any questions while following the described steps feel free to write a comment so that we may help you before you accidentally do something wrong. Your question may also help other people who try to follow this guide.
If you are using Windows on a separate hard disk you can skip the first steps and directly continue with Step 5. If this is not the case for you and you just installed it to a separate partition, it is necessary to do some extra work to convince Windows that there is no difference between our virtual disk and the real hard disk. Before we can create this virtua