Consider the following situation:
You have a custom captured wim of Windows Server 2012 R2 that was built before August 2014.
This wim has served you well, but the amount of updates required on servers built by this image means you want to update this image. In this case, you use the offline servicing SCCM feature to update your image.
You also have a task sequence which installs DotNet 3.5 offline, and you are using this task sequence with standalone media.
You use the following command to do this:
Dism /online /enable-feature /featurename:netfx3 /norestart /all /source:D:\Source\sxs
You will notice that once you start using your newly updated image, your DotNet 3.5 install will fail. This is caused because of two updates which change the source requirements for DotNet 3.5. These are KB2966828 and KB2966827. See here for more information on these updates. Microsoft has long since released KB3005628 which should address this issue for all online systems. However this will still fail with the error: 0x800f081f “The source files could not be found” for offline systems using stand alone tasksequence media and which install DotNet 3.5 using dism. Additionally if you use the powershell command “Get-WindowsFeature Net-Framework-Core” you will see the install state “Removed”. This is because KB3005628 is not included when offline servicing your image.
There are a few options:
1. Rebuild your wim file from scratch using a build and capture sequence and be sure to include KB3005628, then recreate your task sequence media.
2. Add a step to your deploy task sequence to install KB3005628 and recreate just your task sequence media
3. Add a step to your deploy task sequence to uninstall KB2966828 and KB2966827 and recreate just your task sequence media.
For a quick fix, you may want to use option 3, and then revisit option 1 to make the solution more permanent.