If you do not have the media, you may be able to download the evaluation ISO from the Microsoft Evaluation Center to extract the folder. How to Install Using the .cab File Once you have the media mounted or the folder copied to your server (e.g., to C:\temp\sxs ), use one of the following methods to install .NET 3.5: Method 1: Command Prompt (Recommended) Elevated Command Prompt and run the following command (replace D:\sources\sxs with your actual path):
DISM /Online /Enable-Feature /FeatureName:NetFx3 /All /Source:D:\sources\sxs /LimitAccess If you do not have the media, you
In Server 2012 R2, .NET 3.5 is not installed by default. If you try to enable it via or DISM without a source path, the installation may fail because Windows Update is not always accessible or approved in secure environments. By keeping this CAB file in a central
By keeping this CAB file in a central network repository, you can future-proof your Server 2012 R2 infrastructure against legacy application dependencies—ensuring that SQL Server, Exchange, or your critical business software runs without a hitch. to C:\temp\sxs )
For testing, you can download an evaluation ISO of Windows Server 2012 R2 from Microsoft’s website, mount it, and extract the .cab from the sources\sxs folder. (Evaluation copies are time-limited but legally provided by Microsoft.)
: DISM could not validate the CAB or path is wrong. Fix :