Before SQL Server 2012 installation on Windows Server 2012 R2, we have to install .Net Framework 3.5 in the Windows Server 2012 R2 first. However, when we try to install.Net Framework 3.5, we could realize it is not the same to install other features in Windows Server 2012 R2.

At the same time, there is a message prompting us that whether we need to specify an alternate source path.

According to the prompt, we should know that the easiest way is to specify an alternate source path for.Net Framework 3.5 installation.

How can we do that?

1. Prepare Windows Server 2012 R2 installation media, installation disc or ISO file.

2. Insert Windows installation media to server 2012 r2.

Or if we try to install .Net Framework 3.5 on Windows Server 2012 R2 virtual machine, we have to copy Windows ISO file and paste it on server 2012 r2 VM, and then add it to virtual disk.

3. Open Windows installation source file, you would find there is a folder called “SxS”.

This folder is the source path for.Net Framework 3.5 installation.

Now let’s install or add .Net Framework 3.5 to Windows Server 2012 R2.

1. Click Start button to open Administrative Tools and choose “Server Manager”.

Or move the mouse to the upper side of window, and search “Server Manager”, and then run it.

run windows 2012 r2 server manager

2. In Server Manager window, click “Add roles and features”.

add roles and features in server 2012 r2

3. Click “Next” and “Next” again to select “Features”.

You would see .Net Framework 3.5 Features appeared in the features list. Select it and unfold it to just choose “.Net Framework 3.5 (includes .Net 2.0 and 3.0)”. Click Next.

select-net-framework-features

4. Now you would see the prompt that whether we need to specify an alternate source path.

If you have prepared Windows server 2012 r2 installation media and make sure its path, move to the bottom of window and click “Specify an alternate source path”.

select specify feature alternate source path

5. Specify alternate source path.

If we open Windows server installation media, we could find the path of “SxS” folder. Suppose installation disc is in E:\. Generally, source path is E:\sources\SxS. Type it in “Path” box and click “OK”.

specify feature alternate source path

And click “install” button. Few seconds later, .Net Framework Features are installed successfully on this server computer.

install net framework features

Besides Windows server 2012 r2, this way also applies to Windows server 2012 and Windows 8/8.1, if you want to install .Net Framework 3.5 in them.

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