Converting a Dell Windows 7 Professional Reinstallation USB to another Edition

Windows 7 Reached End of Life in January 2020.

Tutorial Video


Dell currently offer only a Dell Windows 7 Professional Reinstallation ISO for Download.

This makes it problematic to install Editions of Windows 7 for example Windows 7 Home Basic, Windows 7 Home Premium and Windows 7 Ultimate.

For such licenses, you can Clean Install Windows 10 using your Windows 7 Product key or generate a Genuine Ticket within your Windows 7 Installation for free.

If you are wanting to reinstall Windows 7 there is no official route to get Windows 7 installation media however fortunately it is easy to convert a Dell Windows 7 Professional Reinstallation USB to a Dell Windows 7 Home Premium Reinstallation USB, all we need to do is modify two files.

Note in the Dell Windows 7 Professional Reinstallation ISO all 4 64 Bit Editions (Home Basic, Home Premium, Professional and Ultimate) or 5 32 Bit Editions
(Starter, Home Basic, Home Premium, Professional and Ultimate) are present. The Professional Edition is Updated to have Driver support for up to 6th Generation Intel Hardware while all other Editions are left unmodified from 2010. In order to install Windows 7 with USB 3.0 Ports, NVMe Storage Controllers it is necessary to Update the install.wim

Another advantage is it also saves a great deal of time updating. On older hardware however the slipstream may not be necessary as you may have USB 2.0 ports only and older Storage controllers which Windows 7 has inbuilt support for.

Selecting the other Editions in the ISO (Dell OEM SLP)

Although you can modify the two files in Notepad, I advise installing Notepad++ to modify the two files:

Open up Windows Explorer, look at your Bootable USB. In my case it is Drive D:\

You may have a different drive letter.

The first file needing to be changed is the EI.cfg file it is found in


Where D:\ is your drive letter. If you are carrying out the slipstream script it will be found in:


Right click this and Edit it with Notepad++

You are only wanting to change one line, this word professional to the desired edition. What you type should all be lower case with no spacing:

I will demonstrate with Home Premium but you can slide across for the other editions.

Home Basic:
Home Premium:

The second file is the SLP.cmd file found in


where once again D:\ is your drive letter. If carrying out the slipstream script it will be found in:


Once again right click it and select Edit with Notepad++

This file contains two lines, the first installs the OEM certificate (which is the same for all Editions) and the second installs the Generic OEM SLP key.

We only need to change this generic OEM SLP key to match the generic OEM SLP key of the Edition of Windows 7 we wish to install. Once again I will demonstrate using Home Premium

Home Basic:
Home Premium:

That's all the Windows 7 Installation Media will now install Windows 7 Home Premium or the Edition you select Opposed to Windows 7 Professional.

You will not be asked what Edition to select during installation and instead be taken straight to the Home Premium License screen:

You will not be asked for a Product Key during installation:

OEM System Locked Preinstallation Activation will occur in the background. You can check your Product Activation by right clicking Computer and selecting Properties:

Your system will be activated if you have an eligible Dell system with a System Licensed Internal Code of 2.1 embedded in it's Legacy/UEFI BIOS.

If you aren't using a Dell System or a Dell System without a SLIC of 2.1, Windows will not be activated:

Converting to a Microsoft Retail ISO

To remove Dell customisation from the Dell Windows 7 PProfessional Skylake Reinstallation ISO delete the $OEM$ folder and EI.cfg file. These are found in:


where D:\ is your drive letter.

If using the Slipstream script these will be found in:


OEM SLP (Non-Dell OEMs)

Install Windows 7 without a Product Key and then copy the OEM folder to C:\ for your OEM and Edition. Run the OEM.slp file which will change the key to your OEMs SLP key and install the OEM cert.

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