Download Windows NT 4.0 Updates

Where can I download Windows NT 4.0 updates, patches, hotfixes or service packs?

The Windows NT 4.0 Downloads page

This page contains all product demos, trial kits, critical patches, service packs, and other beneficial binaries. Check this page for ways to keep your computing systems current and tuned, in addition to evaluation software to help you pilot test new features or versions.
http://www.microsoft.com/ntserver/nts/downloads/
You can also get the updates you need for your personal computer on Windows Update. But if you want to download a patch and keep it for future needs – go to the link provided above.
http://windowsupdate.microsoft.com (for NT downloads make sure you go to the WU site from a Windows NT machine!)
Note for Hebrew Enabled users: When you download a patch, HotFix or service pack, please make sure you select HEBREW from the drop down list of available languages! Do NOT install the High Encryption version of SP6a on your system!!!

Links

Windows NT 4.0 Service Pack 6a
Windows NT 4.0 Downloads page