Microsoft-windows-netfx3-ondemand-package.cab -extra //top\\ Instant

dism /online /enable-feature /featurename:NetFx3 /source:C:\NetFX3_Extra /all /limitaccess : Extracting the CAB bypasses corruption within the CAB’s catalog signature checks. If the CAB’s digital signature is broken but the inner files are intact, extraction recovers them. The Registry Hack: When DISM Refuses to Cooperate If you are truly desperate (and on a non-domain, isolated machine), you can force-enable .NET 3.5 via registry changes. This is dangerous and unsupported by Microsoft , but it works for the "Extra" stubborn cases.

Then manually copy the extracted CAB contents to: C:\Windows\WinSxS\ Microsoft-windows-netfx3-ondemand-package.cab -Extra

dism /online /enable-feature /featurename:NetFx3 /all /source:C:\Users\Admin\Desktop\cab /limitaccess When users report issues with "Extra" parameters, they usually encounter specific error codes. Here is how to solve them. Error 1: 0x800F081F – CBS_E_SOURCE_MISSING Meaning : Windows cannot find the source files. It is looking for the CAB, but your path is wrong, or the file is corrupted. This is dangerous and unsupported by Microsoft ,

dism /online /disable-feature /featurename:NetFx3 dism /online /cleanup-image /restorehealth # Then retry with /limitaccess and the local CAB path Meaning : Your CAB file is for the wrong build of Windows. For example, you took a CAB from a Windows 10 2019 ISO and are trying to install it on Windows 11 24H2. but your path is wrong

Navigate to: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\SideBySide\Configuration