If you are getting this error “0x800f0954” in .net framework 3.5 installations on Windows Server 2019, you can solve the problem by following the steps below.
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Solving Error 0x800f0954
First, delete the folders inside the CBS file. A CBS file is a file that contains logs for both installed and uninstalled Windows Update components. Right-click on the selected files and select delete.
C:\Windows\Logs\CBS
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Secondly, type the following command in PowerShell or cmd and press enter. With this command, we add the sxs file from the iso file.
Add-WindowsCapability -Online -Name NetFx3~~~~ -Source C.\sources\sxs
dism /online /enable-feature /featurename:netfx3 /all /limitaccess /source:c:\sxs
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After running the command, .NET Framework 3.5 will be installed on your system without any errors. However, if the problem persists, try the solutions below.
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As the third, log into Regedit. Enter the record below and correct the “UseWUServer” value to 0. Then restart the computer and try the installation again.
HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows\WindowsUpdate\AU
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