The Cisco SG300-52DC 52-Port Gigabit Managed Switch is now obsolete (past End-of-Life and End-of-Support status).
End-of-Sale Date: 2013-10-07
End-of-Support Date: 2013-10-31
Cisco's End-of-Life Policy
You can view a listing of available Cisco Small Business 300 Series Managed Switches offerings that best meet your specific needs
If you want support information for the Cisco SG300-52DC 52-Port Gigabit Managed Switch documentation, it may be available through Cisco.com Search or in the Cisco Community