Windows 10 on Optiplex 7040: Windows 7 is installed and Windows 10 DVD does not work.

RE: >> Nobody issues a key for 8 or 10 its in the bios.

From: support.microsoft.com/.../windows-10-activation

You bought a new or refurbished device running Windows 10.  

Product key (Preinstalled on your device, included with the device packaging, or included as a card or on the Certificate of Authenticity (COA) attached to the device.)

If I start from scratch using the Microsoft ISO, it asks for a license number.  

If there is no longer a sticker with a license number, as shown in the diagram, what do I use when it asks for a license number?

The procedure is as follows.

You make a bootable USB or DVD for windows 10 creators edition 1703.

You boot and clean install windows 10.

When it gets to the screen where it asks for a product key you press the "I don't have a key Button"

It will then ask Home or PRO.

You have to choose the same version as is on the WINDOWS GENUINE sticker.  If it doesnt say PRO its HOME.

ITEM 7 below is the Windows Genuine Sticker typical on DELL

You then proceed with the regular install.

Once done you go online and Activate windows.  

This should happen automatically.

If it does not download ShowKeyPlus

https://github.com/Superfly-Inc/ShowKeyPlus/releases

Run it and it will show your key if its in Bios.

Dell OEM Licensing

OptiPlex 7040's should have a System License Internal Code (SLIC) of 2.1 to use with Windows 7 Pro OEM and Microsoft Digital Marker (MSDM) with a unique 25 digit Product Key for Windows 10 Pro OEM embedded in the ACPI tables of the UEFI BIOS. More details on looking these up using RW-Everything is available here:

http://dellwindowsreinstallationguide.com/the-oem-product-key-and-oem-system-locked-preinstallation/ 

Activation of Windows 10 Pro using the MSDM

Windows 10 version 1703 installation media should automatically pickup the MSDM key and automatically select the correct Edition of Windows 10 Pro to install (UEFI Boot Enabled, Legacy ROMs Disabled and Secure Boot Enabled). If it does not manually input the key from the MSDM... For best results see here:

http://dellwindowsreinstallationguide.com/download-windows-10-rs2-version-1703-build-15063-creators-update-using-the-media-creation-tool/ 

Activation of Windows 10 Pro using the SLIC

You can activate Windows 10 using the SLIC 2.1. This shouldn't be necessary but will work if for some reason a MSDM table doesn't show up or you still experience activation issues.

Essentially this activation mechanism mimics that of a Windows 7 Pro to Windows 10 Pro upgrade install. 

To do this you will need to reinstall Windows 7 Pro using the Dell Windows 7 Pro Skylake .iso (Secure Boot Disabled and Legacy ROMs Enabled). More details here:

http://dellwindowsreinstallationguide.com/download-dell-windows-7-64-bit-reinstallation-sp2-oem-iso-for-a-uefi-bios/ 

After Windows 7 Pro is installed, alongside the drivers for internet connectivity. Generate a genuine ticket using gatherosstate.exe (from the Windows 10 installation media). Copy the generated genuineticket.xml file to an external hard drive. See here for more details:

http://dellwindowsreinstallationguide.com/the-initial-clean-install-of-windows-10-using-a-faded-windows-7-oem-coa/  

Then perform a clean installation of Windows 10 Pro (UEFI Boot Enabled, Legacy ROMs Disabled and Secure Boot Enabled):

http://dellwindowsreinstallationguide.com/download-windows-10-rs2-version-1703-build-15063-creators-update-using-the-media-creation-tool/  

During installation do not input a product key and install Windows 10 Pro. After installation open the folder C:\ProgramData\Microsoft\Windows\ClipSVC\GenuineTicket and copy the GenuineTicket.xml file. Restart your computer. After the restart the computer's hardware details will be submitted to a Microsoft Product Activation server and your system will be made a Windows 10 Pro Device.

I had to kludge activating my 7040 SFF with Windows 10, even though it has a bundled license.