INSTALL AD MODULE IN WINDOWS SERVER 2008

There is no ActiveDirectory Module available on the Windows Server 2008 Domain Controller, you need to install the Active Directory Management Gateway Service/Active Directory Web Service on the Windows Server 2008 or Windows Server 2008 SP2.  .Net Framework 3.5 SP1 and 2 Hotfix may required if you get the alert "The update does not apply to your system".  
And then, on the Windows 7 client (Domain Computer with Domain Admin Right) you need to install the RSAT and use the following power shell command (case sensitive) to import the Active Directory module:

Import-module ActiveDirectory 

You may download the Active Directory Management Gateway Service/Active Directory Web Service from URL as below:

https://www.microsoft.com/en-us/download/details.aspx?id=2852

You may download the RSAT for Windows 7 from URL as below:

https://www.microsoft.com/en-us/download/details.aspx?id=7887 

2 Hotfix may required as URL below:
https://support.microsoft.com/en-us/kb/969166
https://support.microsoft.com/en-us/kb/967574 

Or you may download the Hotfix KB 969166 from my source, this file I got it from PSS.  Because on the KB 969166 article page not provide the link/source to download.
https://drive.google.com/drive/folders/0B4E0ILJDNhMSdmxodEt3TWZCdlk?usp=sharing