Dear All,

1.A Hacker once added himself onto my Yahoo Messenger list
even after I deleted him, how is this possible and how safe is yahoo ?

2.How does a Hacker come to know if someone comes online
even if it is a totally new ID ?(Yahoo)
That is logging in from a clean system partition both windows
and Linux.

3.Is it possible to track a person based on his Modem MAC,Phone
number used to connect the ISP. Is it possible to install a sniffer
in the ISP.

** My ID's hacked and I have seen the Hacker
Hack other ID's on my friends list.Weird.
I came to know after I asked my friend whether
he was logged on and he said no...?