When I receive a virus and look at the e-mail's properties to see where it is coming from I often see:

Received from: abc.com (an IP address)

where abc.com is my ISP server's name, and IP address in brackets has nothing to the with my ISP. When I trace the IP address I can see where it is coming from and often many viruses come from the same IP address. Is this IP address genuine and shows where the virus has been posted.

Anyone knows ?