Q: How can I enable the Active Directory (AD) Recycle Bin feature to provide longer protection for the deleted objects in my AD forest?
A: Microsoft introduced the AD Recycle Bin in Windows Server 2008 R2. This feature isn't enabled by default and requires the Server 2008 R2 forest functional level. To enable it, you can use either Windows PowerShell or Ldp.exe. TechNet's Active Directory Recycle Bin Step-by-Step Guide describes how to use both tools in detail.
Inand later, the Active Directory Administrative Center (ADAC) includes a GUI option to enable the AD Recycle Bin. To enable it, open ADAC, click your domain's name, and select Enable Recycle Bin from the Tasks menu. Alternatively, you can right-click your domain's name and select Enable Recycle Bin from the context menu.