Hi WSUS Admins:
We’ve noticed some confusion about the recently released updates for Microsoft .NET Framework 3.5 SP1. So, let’s see if we can help clarify the differences in the packages. These updates apply to x86 and x64 computers. The detailed update descriptions describe both the platform and OS architecture that apply for each of the updates. You’re also likely wondering about the differences in the update titles. Here are the differences:
1. The update titled “Microsoft .NET framework 3.5 Family Update (KB959209)” updates computers already running .NET Framework 3.5 SP1 with the latest compatibility fixes. So, if you only want to update existing .NET Framework 3.5 SP1 computers with the latest fixes, then approve these packages.
2. The update titled “Microsoft .NET Framework 3.5 Service Pack 1 and .NET Framework 3.5 Family Update (KB951847)” will upgrade computers with .NET Framework 2.0, 3.0, 3.5 to the latest version of the .NET Framework 3.5 SP1, and will also apply KB959209 (#1 above). If you want to upgrade/update all of your computers to the latest version of the .NET Framework and apply the latest compatibility fixes, then approve these packages.
If you know you only need the latest compatibility fixes for 3.5 SP1, then we recommend you only approve the Microsoft .NET framework 3.5 Family Update (KB959209). Otherwise, we recommend that you approve the second update.
The WSUS team