Is it possible for someone to access my HD even though I am running a firewall?

This is probably just an empty threat from some net.k00k with a grudge
but I'd appreciate your advice.

Someone on a web forum I visit is claiming that they have accessed my
hard drive, stolen my personal details and installed files to 'prove
that they were there'. According to this person, all they needed was
my IP address to do this.

I am running the latest version of Zonealarm, check for
viruses/trojans/spyware on a regular basis, have not run any strange
files or opened any attachments and have done nothing besides allowing
this person to discover my IP address. As far as I know, my machine is
clean and as secure as it can be.

Is there any possibility that my security has been compromised? If so,
what steps can I take to prevent someone doing this again? Thanks.
Received on Mon Nov 21 02:36:41 2005