Malicious Code has become increasingly complex and infections involve more system elements than ever before. No Anti Virus system can prevent the infection to affect the computer prior to its installation. It looks like, your system has become infected, the tools listed below should aid you in repairing the damage.
If you are on a network or have a full-time connection to the Internet, such as a DSL or cable modem, disconnect the computer from the network and Internet. Disable or password-protect file sharing, or set the shared files to Read Only, before reconnecting the computers to the network or to the Internet. Because this worm spreads by using shared folders on networked computers, to ensure that the worm does not reinfect the computer after it has been removed, it's suggested to have sharing with Read Only access or by using password protection.
It looks like your systems is infected by W32.Downadup or ot's varient.
W32.Downadup.C may block access to Symantec Web sites and network addresses. I'm sure www.microsoft.com
is also not working in your machine.
Get the Removal tool from
More information about how to remove it.
All the best.