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SCUP 2011 and File Digest errors

This one has been bugging be for quite some time...

Sometimes, when you've published an update from SCUP to WSUS as metadata only, it fails to publish the full content later and gives an error of "incorrect file digest".
What's going on here?
This is where the publisher has created an updated binary for the same release, but not updated the Origin File Digest in the metadata.
When SCUP imports a update, it stores a SHA-1 Base64 hash of the file which is held in the SCUP database. When you go to publish "full content", it compares the hash of the downloaded file with that in the database. When the don't match, you get the file digest error.
Ultimately, this is a mistake on the part of the vendor, but they're pretty inconsistent at fixing them (Dell being a particular offender).

So how do we fix it to get that critical update out?

Download the binary directly from the vendorGet the SHA-1 Base64 encoded of the file (I used online-convert.com)Take a cop…

Repairing non-booting Windows 2012 R2 and others

If you're stuck in a "Preparing Automatic Repair" boot loop that always takes you back to the blue screen of unhelpful menu options:

Disable Automatic repair

Get to the recovery command prompt

bcdedit /enum

Get the name of the Windows entry (likely to be {default}

bcdedit /set {default} recoveryenabled No

Reboot

Now instead of getting into the loop of a failing repair it'll show you the real problem that it's failing to fix. This is likely to be a corrupt file. In my case it was c:\windows\system32\drivers\cng.sys which I copied from a working server that was at the same patch level.

All things WSUS

A variety of fun things that have dug me out of multiple WSUS related holes

Cleaning Unused Updates Getting reset server node is pretty common with this, so spin up SQL Management Studio and run:

Windows has no updates from WSUS Had this after creating a new VM from a fully patched VHDX. Updates from WSUS would only work after checking against Microsoft Update first.
1. Stop Windows Update Service 2. Delete contents of c:\windows\softwaredistribution 3. Check for Updates against WSUS again