I went to the "Previous WDK" download page this morning. Microsoft has removed all but the very latest WDK:
Previous WDK versions and other downloads - Windows drivers | Microsoft Learn
Older versions are still available through MSDN, but this sends a pretty strong signal.
WDKs should be backwards compatible, is there a reason you'd want an old one?
They aren't backwards compatible for all releases of windows. Win7 for example.
Thanks for pointing that out, yeah, compatibility with older targets like Win7 has definitely been an issue. Some older WDKs had specific headers or behaviors that don’t line up cleanly with the newer kits, especially when targeting legacy driver models. It’s a bit of a gap now that those versions are no longer directly available.
None of those currently impede my work, but I definitely encounter scenarios where legacy stuff cannot be eliminated for 
reasons . This change adds just enough friction that it may cause some people who otherwise previously just couldn't be bothered to now put in the work to update their kits/compilers/OS targets, which is overall a good thing.
We want old ones because the Windows 10 IoT enterprise LTSC are still being serviced.
It looks like they still have a number of older EWDK (Enterprise WDK) available, at least from Windows 11 22H2. But you might need even older?
We have LTSC products in the field as far back as release 1809. The servicing for this product is not supposed to end until 2029.
We have the WDK 1809 installer but yes we need this WDK.
Thank you all for highlighting some of the real-world challenges that come with the removal of older WDK versions.
We fully acknowledge that there are valid scenarios where legacy WDKs may still be needed — such as targeting older OS releases like Windows 7, 32-bit kernel mode driver development for Windows 10, or ongoing support for LTSC versions like Windows 10 IoT Enterprise. We understand the friction this introduces for teams maintaining long-lived products or devices in regulated or embedded environments.
That said, Microsoft has made a strategic decision to consolidate our support and investment around the most recent WDK and EWDK versions. These modern kits offer improved security, better tooling, and alignment with the latest compiler and SDK toolchains. Encouraging the ecosystem to adopt newer kits allows us to deliver more robust support, address issues more quickly, and ensure developers are building on the most secure and performant foundation available.
We recognize that this transition may leave some gaps — particularly for developers who need to reproduce legacy builds or maintain compatibility with older servicing baselines. If you’re facing blockers or have scenarios where the newer kits do not meet your needs, we want to hear from you. Your feedback helps us evaluate potential mitigations and plan for broader ecosystem needs.
Please reach out to us directly at wdkfeedback@microsoft.com or complete the feedback form. We’re committed to working with you to ensure your development needs are understood and, where possible, supported.
Thank you for being a part of the Windows driver development community and helping us move the platform forward.
Disk space costs essentially nothing. There is absolutely no reason for a web resource to EVER go AWOL. Put them in an archive section, if nothing else. This is quite disappointing.
We believe the decision to retire the older kits, while ensuring support for developers impacted by the change, was the right step to uphold the security and reliability of Windows drivers. A key consideration was also reducing exposure to CVE-2024-29187
Hope this helps clarify
So instead of moving the download under a separate page with explanation of the vulnerability and details on possible workarounds (which, from what I understand, is as trivial as "change permission on TEMP for the duration of installation"), you just completely remove the tools, that are crucial for developers to keep supporting their products. A brilliant solution!
Microsoft authorized distributors are still selling licenses for
Windows IoT Enterprise LTSC 2019 and
Windows IoT Enterprise LTSC 2021
Microsoft says these versions are currently supported.
We bought this product on good faith believing that Microsoft would honor its commitment to support this product.
