In addition to the current answer, here is a guide with some alternative formatting and pictures (although the steps mostly remain the same. Adapted from Enable Aero Desktop Experience in Windows Server 2008 R2
First, installing the desktop on Windows Server 2008 R2 :
- Click Start> Control Panel> Programs and Features> Turn Windows Features On or Off.
- In the Features Summary section, click Add Features.
- Check the "Desktop Experience" box.

Enter additional functions if necessary
- Click Install, you may have to restart your Windows computer.
Next, enable the theme service :
- Click Start> Control Panel> Administrative Tools> Services.
- Click Themes.
- In the Startup Type list, select "Automatic" and click "Apply."
- In the "Service Status" section, click "Start" and then "OK."
Finally, choose the Aero theme :
- Right-click on the desktop and select "Personalize."
- Click Themes.
- In the Aero Themes section, select the Aero theme.
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