Home > .NET 3.5, PowerShell, Windows2012, Windows2012R2 > HOWTO: Add .NET 3.5 to Windows 2012 or 2012 R2

HOWTO: Add .NET 3.5 to Windows 2012 or 2012 R2

This has been something I’ve had to keep flipping back to my notes for, so I figured I’d jot it down.  Various products, such as vCenter Server, require the installation of .NET 3.5 on Windows 2012/2012 R2.  Doing so, however, is not as ‘simple’ as finding the download and installing it. This component is actually a Windows Feature, and must be installed via this method. 


Above is a screenshot from the Add Windows Roles and Features wizard.  Do NOT check the box for Application Server and click NEXT.


Next, you can select .NET FRAMEWORK 3.5 FEATURES, and specifically the sub-item of .NET 3.5 FRAMEWORK.  Click NEXT.


If you see the above screen, prompting for .NET 4.5, then in my first step above – you actually checked the APPLICATION SERVER role, which has .NET 4.5 as mandatory.  As we don’t need it, you should go back and uncheck it. 


Note that highlighted yellow bar.  The reason you’re seeing this is that it’s informing you that the actual components for this are NOT cached on the local system.  You need to click on the other circled link, to SPECIFY AN ALTERNATE SOURCE PATH


Here you can specify the path.  In this case, I’ve double clicked and mounted the Windows 2012 R2 with Update ISO so it is mounted as the E: drive – thus, I can specify E:\SOURCES\SXS as the source folder.  Click OK then click INSTALL on the previous screen when it returns.


Click FINISH.  While it doesn’t force you to reboot, it might be wise to both check for any Windows updates related to .NET 3.5 and reboot as well.

Some additional comments:

Network UNC paths – I’ve had mixed success with unpacking the ISO to a network share and specifying the name.  Usually I’ve been short on time, so couldn’t spend the time to troubleshoot.  Suspected suspected culprits are:

  • DFS-N name spaces give it grief
  • Long (>64) character UNC paths cause issues
  • Spaces in the path can cause grief
  • The MACHINE account for the computer doing the installation doesn’t have rights to the share, even if the USER does. 

Command line installation – you can perform all of the above with PowerShell using the command:

Install-WindowsFeature Net-Framework-Core -source \\network\share\sxs


Reference: http://technet.microsoft.com/en-ca/library/dn482068.aspx

  1. No comments yet.
  1. No trackbacks yet.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: