How many times did you have to restore your Windows operating system but have lost your recovery CDs or not created them?
Luckily there is a way! All you need is a file Window ISO (that is, the entire Window function in a file) and free Ei.cfg Removal Utility which deletes a key file within the former by letting you install any Window version.
Regarding the installation versions of Windows 7 and 8, there is some peculiarity.. The specific versions are designed to match the key of product. That's why you can't on a Windows 7 Home PC Premium to install Windows 7 Professional, even if you have a CD for the latest.
Here comes the Ei.cfg Removal Utility. If you somehow fall into the hands of for example a CD with Windows 7 Home Premium and licensed for the same operating system, Ei.cfg effectively creates a universal Windows ISO that will install any version that matches your product key.
The process is simple. Load a friend's install CD / DVD, copy ISO to your hard drive, then run Ei.cfg and then use the tool Rufus to boot the "teased" ISO on a flash drive to install Windows on your computer.
Now, just boot from the flash drive and choose to install the version of Windows you are licensing for. Type your key and you are ready to continue! And remember, your key will only work for the version it's intended!
If you can not find an ISO for Windows while you have a valid license, Microsoft has taken care of. There is an official ISO of Window 7 SP1 here & Windows 8.1 here.
