Windows update KB3004394 issues

Same problem for me. W7SP1 Pro x64 (US English). Windows Defender will not start ("stub received bad data"), Windows Update no longer works (error code 0x800706F7), Internet Explorer 11 will not install (log file says "failed to install local package"), Microsoft Security Essentials will not complete installation.

Removed KB3004394 and all seems to be back to normal.

A colleague's PC running W7SP1 Pro x86 (Brazilian Portuguese) will not install Net Framework 4.5.2 from Windows Update after KB3004394, so maybe the same problem occurs with the 32-bit version of Windows 7. But I do not have access to his computer to check this.

I haven't had any problems on 2 machines running Windows 8.1 Pro x86.

Re the Windows 8.1 patches: Windows Update at first offered to install an update to Microsoft Silverlight, but now it has disappeared (I did not have WU configured to automatically install updates, so the Silverlight update has not been installed). I've also read a comment on na Austrian site about this update causing problems navigating many sites that use Silverlight.

So it seems that Microsoft has released two buggy patches...

Susan,

On my PC it is showing as important, not optional

Despite having removed and re-installed this update twice (i.e. now on my 3rd installation), my PC remains unafflicted by any of the symptoms reported in this thread.

Just a thought - maybe I am unaffected because I always manually install all Microsoft Updates as the administrator? (Leastways all those that I choose to take)

I have noticed that virtual machines built through Oracle's VMBox fail to start if Windows Update KB3004394 is installed.  After I uninstalled the update the virtual machine issues we resolved.

It's how you set your updates.  If you have "show me optional updates in the same manner as important" they show up on the main screen.  If you untick that box, they are on the second tab.

For me here, they are optional as I have the box unticked.

But bottom line uninstall that update everyone and hang loose.

Hang loose guys .  Seeing If I can alert someone. In the meantime this is in the optional section of updates.

Root certs are supposed to be silent updates to Windows 7 and not even offered up via Windows update so unless something has changed they shouldn't even be in the WU detection in the first place.

Hi Susan,

Thanks for looking into this.  Re the problematic Win 7 64-bit SP1 Home Premium system, it did recently get cleared of adware infections but is now known to be clean.  Process of cleaning was thorough and painstaking, in fact.  There are no remnants left over.

Primary issue, from what I can see, is that Windows UAC sees all windows system files as unsigned.  Removal of KB3004394 reverts all system files to signed and issues are gone.

From what I understand, this update speeds up the certificate update program from once a week to less than 24 hours, is that correct?  So if Microsoft issues new certs they will be installed silently in less than a day?  Reason for this is enhanced protection?

Just so you know, this update appeared not in the optional section of WU, but in the main section.  It was not offered as an optional update as it normally would. 

If optional, I would've declined.

One troubleshooting step not taken would be to disable the Avast! firewall and leave the Windows firewall enabled and then try to install KB3004394.  Will report back as I've noted a system slowdown with Avast Internet Security installed; suspect avast is examining some windows system files when they are called and it seems to take some time to clear and proceed. 

Last month there was an issue with avast and a WU update and wonder if this is similar.  Will report back if any change is seen.