Hi.
You must read this.
http://www.theeldergeek.com/network_dde_dsdm.htm
http://windows.fyicenter.com/188_Performance_Services_netdde.exe_Service__Network_DDE_DSD.html
http://www.digitalsupporttech.com/spdb/Startup/52502_Startup_Net_DDE_dsdm_Service_en-us.htm
And run Malwarebytes (freeware)
http://www.malwarebytes.org/