If you’re still waiting faithfully to download and install Windows 8.1 Update from legitimate source, i.e. Microsoft, the wait is finally over. As scheduled on April 8th, 2014, Microsoft has published the Windows 8 Update as KB2919355 on Microsoft Download Center,
even though you probably have to wait for an hour or two more to getand also distributed the updates through Windows Update. Windows Update is expected to made available Windows 8.1 Update on 10am PST (Pacific Time), which is the time the Patch Tuesday normally rolled out.
Windows 8.1 Update can be downloaded from the Microsoft Download Center at the following URL:
Windows 8.1 32-bit (x86): http://www.microsoft.com/en-us/download/details.aspx?id=42327
Windows 8.1 64-bi6 (x64): http://www.microsoft.com/en-us/download/details.aspx?id=42335
Windows Server 2012 R2 Update: http://www.microsoft.com/en-us/download/details.aspx?id=42334
There are multiple files available for this download, and you will be prompted to select the files you need when you click on the “Download” button. The files available are, together with their direct download links:
64-bit Windows 8.1 Update
32-bit Windows 8.1 Update
Windows Server 2012 R2 Update
Windows 8.1 must be installed in the following order: KB2919442, KB2919355, KB2932046, KB2937592, KB2938439, and KB2934018. KB2919442 is servicing stack update and prerequisite for Windows 8.1 Update, and has already been released via Windows Update previously. So your system may already installed with KB2919442, otherwise download it from here.
The Spring Update changes the build number of Windows 8.1 to 9600.17041.amd64fre.winblue_gdr.140305-1710.
One thing of note is that, the official Windows 8.1 Update also has slight differences from the Windows 8.1 Update released via MSDN/TechNet. Most prominently is that the KB2949621-v2 has been removed from the package, and superseded by KB2934018 which supposed to include everything from KB2949621. If you’ve installed KB2949621-v2, you can uninstall it and then install KB2934018. As the result, Windows 8.1 with Update ISOs previously leaked from MSDN/TechNet may also have been updated to newer version by Microsoft to reflect the changes.
If you manually install Windows 8.1 Update, remember to check for other updates in Windows Update too, as there are several other updates which are not officially part of Windows 8.1 Update available, including KB2939087 which was initially thought to be part of Windows 8.1 Spring Update, and has been updated and changed on official release since the leak.