Microsoft rereleases botched December patch KB 3004394 -- and it works

The first version of the Windows Root Cert patch caused massive headaches, but this new release has slipped by almost unnoticed

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Those of you who suffered through December's Black Tuesday patches probably remember the Windows Root Cert patch KB 3004394. On Windows 7 and Windows Server 2008 R2 PCs, that patch caused all sorts of mayhem: Windows Diagnostic Tool errors, Windows Defender errors, weird UAC prompts, blocked installation of some drivers, and new patches that were prevented from installing.

Microsoft pulled the bad patch just two days after releasing it, recommended that people manually uninstall it, then released a "silver bullet" patch, KB 3024777, whose sole mission was backing out the bad KB 3004394.

With no fanfare and only a brief mention buried in a lengthy listing, Microsoft rereleased KB 3004394 last week, on February's Black Tuesday. The silence has been deafening. I see no confirmed reports of problems on any of the usual sites. It certainly looks like this version has fixed the (voluminous) problems of its forebear.

If you manually download the Windows 7 updates from the KB 3004394 page, the three new patches are identified as:

  •  Windows6.1-KB3004394-v2-x86.msu (for Windows 7 32-bit)
  •  Windows6.1-KB3004394-v2-x64.msu (for Windows 7 64-bit and Server 2008 R2)
  •  Windows6.1-KB3004394-v2-ia64.msu (for IA-64 based Windows Server 2008 R2)

All of them have a published date of 2/10/2015.

The Windows 8, 8.1, Server 2012, and 2012 R2 versions all appear to be unchanged from December.

t/h JB, MM