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Well, this is a showstopper for me. I'm in the Release Preview ring & installed 1903 (18362.30) yesterday . Update went fine. No issues experienced.
Got a Cumulative Update to install today (KB4495666). Installed it & rebooted. Build is now at 18362.53. .NET framework was disabled & 90% of my applications will no longer run! In "Control Panel/Programs and Features/Turn Windows Features on or off", ".NET Environment" is unchecked. If I check it & hit "OK" it take about 10 seconds & says "Windows completed the requested changes". The .NET Environment, however, is still unchecked when I go back to "Turn Windows Features on or off" & >NET applications still don't work.
I've uninstalled all of the updates installed today (KB4495666 & KB4493478), but .NET is still utterly broken. I've read that this was an issue prior to the release of 18362 to the Release Preview ring but was supposed to have been fixed. Looks like this MAJOR bug was reintroduced with the cumulative update?
Locked Question. This question was migrated from the Microsoft Support Community. You can vote on whether it's helpful, but you can't add comments or replies or follow the question.
KB4495666 is an update for Windows Insiders ONLY.
Those who are not part of the Insiders Program and therefore are not exposed to untested software have nothing to fear.
Just wanted to straighten that out as there seemed some confusion on that point.
https://support.microsoft.com/en-us/help/4495666/windows-10-update-kb4495666
Wow, I found a DISM command that appears to have fixed this. It worked on 18362.86 that was showing the same symptoms, with NetFx3 unknown, etc. and the strange list of Features in optionalfeatures.exe.
If anyone still has a system in this state you can try it. It involves using a single command to enable 5 of the still-listed NetFx Features at once. Below is all one line:
DISM /Online /Enable-Feature /All /NoRestart /FeatureName:Microsoft-Windows-NetFx3-OC-Package /FeatureName:Microsoft-Windows-NetFx4-US-OC-Package /FeatureName:Microsoft-Windows-Client-EmbeddedExp-Package /FeatureName:Microsoft-Windows-NetFx3-WCF-OC-Package /FeatureName:Microsoft-Windows-NetFx4-WCF-US-OC-Package
You can see the list of the 5 features at the top of the below screenshot, with the required command at the bottom.
I had the same issue.
After upgrading to 1903, .NET 3.5 disappear from appwiz.cpl. Powershell broken due to .NET loss, and many apps too.
Sfc /scannow, Dism /Online /Cleanup /[ScanHealth, CheckHealth, or RestoreHealth] didn't help.
I just add to do these line in cmd as admin to solve that one :
I see that a user mentionned that, you could also do that with dism utility.
I think they are already fixing this one.
The repair tool doesn't work, but it does give me a "Failed" result, recommending to reinstall, which I can't do. The manual .NET installer also doesn't work.
There are more reports of others experiencing this issue appearing in the Feedback hub now.
Which .NET framework are you talking about ?
There are two of them. In my system one of them ( .NET Framework 3.5 ) always comes disabled ( unchecked ) by default. The other ( .NET Framework 4.8 ) comes partially enabled.
If I check the box besides .NET Framework 3.5, a dialog window opens, asking me to allow Windows Update to download necessary files.
After the files are downloaded and installed, I have .NET Framework 3.5 installed.
