Stranger server behaviour after Conficker infection

I have a server running Windows 2003 w\sp2, running NOD32 v4, that had been infected with Conficker and every now and then mysteriously goes offline. The server responds to ping/SNMP but all services go offline. After hard rebooting the server all comes up fine, but days later the same incident will recurr. I have all NOD settings configured as per:
http://kb.eset.com/esetkb/index?pag...earch&viewlocale=en_US&searchid=1262878604958

I don't know whether I'm experiencing a virus/security issue, or if NOD is causing the problem. There is nothing showing up in NOD log, and 2003 event viewer only shows the server going off the network i.e. W32time can't contact time server. This is happening on more that one server within the domain, so it's not unique to one server.

Baffled by this mysterious problem. HELP!

 

make sure you removed all malware, try suggestions
https://www.wilderssecurity.com/showpost.php?p=1533481&postcount=3