My son seems to have had a hacker at his computer. He has firewalls installed and countless virus checkers, security etc., but nevertheless it has happened. He cannot use the CD drive now - it appears to be locked - tells him there is no space. Data seems to be going out down the line when he connects. Does anyone have any ideas, please? Thanks

Can you post the exact error messages?

What makes you think that data seems to be going out when he connects?

What makes you suspect a "hacker"?

Is the hard drive ok? Does XP work? Is it only the CD drive that is a problem?

There are 2 CD drives. The first has a capacity of 14.6GB, the second 99.8GB. When he tries to transfer files from "my docs" onto the CD drive, both say "0 Free". The same CD on my laptop shows plenty free and there should be on his.
The computers at his place of work were hacked a few days before - all the passwords were changed. My son has his own website published, but when he tries to add/delete email addresses from it, using his home computer,he is locked out.
I cannot say why he thinks data is being taken from his computer - he doesn't really explain it! Just says it is happening!
Everything else on the computer seems to be working perfectly.
This may all sound a bit silly - I am no expert. He is just so worked up over it I am trying to help. Strangely, his blackberry phone showed problems at the same time.
Thank you for trying to help.

just to clarify:

There are 2 CD drives. The first has a capacity of 14.6GB, the second 99.8GB.

CD drives? Do you mean Hard drives?

The same CD on my laptop shows plenty free and there should be on his.

The same CD?

Sorry if I am missing something here.

Perhaps look in Disk Management for status of drives:
Rt. click "My Computer" then click "Manage" then "Disk Management"

Let us know what's up there.

As to the web site: he is able to access it but not make changes on it?
Is he recognised as the owner?