Can't enable .NET Environment in Windows 10 1903

The abnormal list is displaying some sub-features of the missing top-level features. The Parent features have vanished. The Parent features also do not appear in DISM/PowerShell. Even when Disabledor DisabledWithPayloadRemoved, the Features should never vanish from the list that is displayed with DISM /Online /Get-Features /Format:Table.

In Windows Server you can eliminate all parts of .NET, but there is a command that can restore it all, as long as you can point to the matching WIM file from the Windows Server install ISO as a Source.  This same command does not exist for Windows 10 client and you can't run the command from a server to affect a Windows 10 client.  Below is the Feature list from Windows Server that names some of the .NET Features on Windows 10 that are missing on devices that have this problem.

Thanks for the quick reply Don. I tried restarting from Features several times. Says it completed successfully but after rebooting still not active. DISM failed also. My Features list looks like the 2nd (right? I'm on a phone) with the ASP.NET4.8 listed.

You can try some of the fixes that were described here in this thread. Sometimes they work.

Check if the .NET features appear as they normally do in your Control Panel Features. If so,  NET can probably be fixed using DISM or PowerShell.

Normal list is potentially repairable:                                            The appearance on the right has no known fix that I have found:

I inadvertently upgraded to 18362 and now .NET will not start. I tried to restore to several earlier restore points and that fails also.

I tried to install Insider Preview 18885.1001 and that failed also. 

My home automation software runs on this system and needs .NET 4.0.

When is Microsoft going to resolve this issue? 

This is unacceptable.

I have a Hyper-V VM in which I have replicated this issue. I have tried Windows Reset as well as an in-place upgrade (to the same build number).  Neither one fixed it. The VM was originally a clean install of build 18362.30.  I am unable to remove the .30 CU.  It keeps upgrading itself to 18362.53, although that CU I can remove.

In my research, there seems to be some indication that adding KB updates or Language Packs when these .NET symptoms exist, may make it impossible to repair. Uninstalling the KB update or Language Pack has sometimes helped (with Servers).

So the simplest fix is a total wipe and clean install. I did not have this issue until I totally uninstalled .NET on this VM.  It is the missing Parent Features that are blocking the reinstallation of .NET Features.  The Parent Features are not the same type of Feature On Demand as what we see in the Windows Features Control Panel.

An example of one of the chains of .NET features from a working system is below.

PS C:> Get-WindowsOptionalFeature -Online -Verbose -FeatureName NetFx4Extended-ASPNET45                                                                        VERBOSE: Target Image Version 10.0.18362.53

FeatureName      : NetFx4Extended-ASPNET45

DisplayName      : ASP.NET 4.8

Description      : ASP.NET 4.8

RestartRequired  : Possible

State            : Disabled

CustomProperties :

                   ServerComponent\Description : .NET Framework ASP.NET 4.8

                   ServerComponent\DisplayName : ASP.NET 4.8

                   ServerComponent\Id : 429

                   ServerComponent\InstallWithParentByDefault : true

                   ServerComponent*Parent : NET-Framework-45-Core*

                   ServerComponent\Type : Feature

                   ServerComponent\UniqueName : NET-Framework-45-ASPNET

                   ServerComponent*NonAncestorDependencies\ServerComponent\UniqueName : NET-Framework-45-Extended*

                   ServerComponent\Deploys\Update\Name : NetFx4Extended-ASPNET45

                   ServerComponent\Version\Major : 4

                   ServerComponent\Version\Minor : 5