Are patch dependencies handled by WU?

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Looking through my WU history I noticed that some updates in 2016 had failed (maybe I was on auto updates then). It got me wondering if WU checks for dependencies. This might also occur if a monthly update is hidden (maybe on advice of this forum) and then the next months updates come along.

What if there are some dependencies? How does WU handle this?

 

Alan

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It sounds like only 4 or 5 patches failex to install, from what you’ve written. If that’s the case, let us know exactly which ones they were, and we can let you know if they’ve been superseded or not. For those that have been superseded, we can probably tell you the current patch that’s replaced them. That way you can check to see that you’re up to date on your patches.

If you take a thorough look at the list, you may find that the patches that failed to install the first time were later successfully installed, so please do that before posting a list of the failed patches.

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That’s kind of you Anon. Many of the failed were eventually reinstalled. I found just 1 that was not:

2018-03 Security Monthly Quality Rollup for Windows 7 for x64-based Systems (KB4088875)     Installation date: ‎25/‎03/‎2018 14:34   Installation status: Failed  Error details: Code 80242016

My understanding (and I may be wrong!) is that these rollups actually contain multiple patches so presumably one cannot simply say Mar 19 rollup can be skipped and Apr 19 rolloup will make the system good again.

Windows 7 SP1 Professional 64 bit AMD A8-7600 Asus A88XM-Plus

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The Security Monthly Quality Rollups are CUMULATIVE. That means, for example, That the April Rollup contains the fixes that were in the March Rollup (and fixes from before that) plus any new fixed. And the May Rollup contains the fixes that were in the March and April Rollups plus any new fixes. And so on.

So if you happen to skip the March Rollup, installing the April Rollup should bring you up to date. Etc.

2 users thanked author for this post.

Alan_uk, walker

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Thanks PKCano This means that over time the rollup get bigger and bigger. Sometimes they take ages to download, even weeks after a patch Tuesday. As other websites are OK then it must be a bottleneck at MS.

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No, actually the “inordinate” (for lack of a better word) amount of time for the patch to download is not spend actually downloading the entire thing. The file is downloaded by the time the progress bar reaches the 5% mark. The rest of the “downloading” time is spent by the TrustedInstaller.exe process, along with svchost.exe and a couple of other processes poring over the entire package trying to decide what’s applicable to your system and what isn’t. After these decisions are made, the TrustedInstaller.exe process then proceeds to get the ball rolling on actually installing what is needed.

I’ve also read that Windows Update also occasionally downloads what are called “deltas”, or files that have changes from one month to the next, which are smaller than the whole file size of the monthly rollup quoted by Windows Update. How one can tell that these have been downloaded instead of the entire thing, I’m not too sure.

All I do know is what I’ve seen after looking in Task Manager while the monthly update has been “downloaded” and installed, and what I described in the first paragraph above is all that I’ve ever seen happen during the Security Monthly Quality Rollups’ installations.

I hope this helps, and if anyone else has any additional info and can add clarity about the “deltas”, please feel free to chime in!

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That’s interesting Anon. I shall look carefully next time at my download traffiic and compare to the percent WU.

Alan

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