Microsoft have acknowledged feedback on the lack of downloadable installation media for all Windows 7 OEM and some Windows 8.1 OEM editions.
Windows 10 TH2 will accept Windows 7 OEM and Windows 8.1 OEM product keys.
The Windows 10 Insider Preview .isos are available here:
https://www.microsoft.com/en-us/software-download/windowsinsiderpreviewiso
These .isos automatically input:
- Dell Windows 8.1 (Home) OEM keys (tested)
- Dell Windows 8.1 Pro OEM Keys (tested)
- Dell Windows 8.1 (Home) with Bing OEM Keys
- Dell Windows 10 Home OEM keys
- Dell Windows 10 Pro OEM Keys
They also accept:
- Windows 7 Starter OEM COA keys
- Windows 7 Home Basic OEM COA keys
- Windows 7 Home Premium OEM COA keys (tested)
- Windows 7 Professional OEM COA keys (tested)
- Windows 7 Ultimate OEM COA keys
They currently do not support Single Language or N Editions:
- Windows 7 Starter N OEM COA keys
- Windows 7 Home Basic N OEM COA keys
- Windows 7 Home Premium N OEM COA keys
- Windows 7 Professional N OEM COA keys
- Windows 7 Ultimate N OEM COA keys
- Windows 8.1 (Home) Single Language OEM keys
- Windows 8.1 (Home) Single Language with Bing OEM keys
- Windows 8.1 (Home) N OEM keys
- Windows 8.1 Pro N OEM keys
- Windows 10 Home Single Language OEM keys
- Windows 10 N OEM keys
- Windows 10 Pro N OEM keys
If you input a key from an N Edition or Single Language Edition you get the error message.
When these .isos are released on the main track covering the N and Single Language Editions Windows OEM will have a proper digital distribution.
The fact that Microsoft have listed 2 Editions on 1 .iso suggests that they might list all 5 on the one .iso like they did with Windows Vista/7 which suggests they might be taking into account additional feedback I left and this will end all the end user problems regarding Windows Edition and UEFI BIOS embedded product keys:
I am thus recommending all out of warranty Windows 7 users without installation media to install Windows 10 TH2 Insider Preview. My updated guide is available here:
http://dellwindowsreinstallationguide.com/download-windows-10-technical-preview-iso/
If you are running an unsupported edition install the Windows 8.1 90 day Evaluation Preview or Windows 10 Evaluation Preview:
http://technet.microsoft.com/en-us/evalcenter/hh699156.aspx
Windows 10 TH2 covering all Editions should be released on the main track before the 90 day Evaluation preview expires.