Trojan Horse/computer security question

[Alvaro]

Was wondering if anyone can advise me on a possible
problem that's cropped up on my home PC.

I use Microsoft Windows XP Home Edition. I ran a free
security check from Systemac, and it identified two
Trojan Horses in its system. I was able to delete one of
them with no problems, but the other, Backdoor.Coreflood
(in a C:\WINDOWS\system folder the contents of which are
a complete mystery to me) seems impossible to deal with.
The problem is that whenever I try to delete the file in
question, a message comes up reading: "Cannot delete: It
is being used by another person or program. Close any
programs that might be using the file and try again."

I'm wondering what kind of a threat this Trojan poses,
and what I can do about it. According to Systemac, it's
been on my computer since August this year, but when I
scan the supposedly infected file with Norton AntiVirus
it gets a clean bill of health. I've not noticed anything
amiss while using the computer, and I haven't received
any mysterious bills for things, but the idea of a hacker
gaining remote access to one's computer is never a
pleasant one.

Does anyone know of any way in which I can eliminate
Backdoor.Coreflood, ideally without having to splash out
any money?

 

[Doug Knox MS-MVP]

http://www.symantec.com/avcenter/venc/data/backdoor.coreflood.b.html
http://securityresponse1.symantec.com/sarc/sarc.nsf/html/backdoor.coreflood.html

There are different variants of this worm, so make sure you get the correct
one. The pages above include the instructions for removing this trojan.

 

[Jan Kåre]

See Symantec for detailed info:
http://securityresponse.symantec.com/avcenter/venc/data/backdoor.coreflood.html

Symantec says ".....The Trojan connects to an IRC server and gives control
of the infected computer to a hacker..... "
Removal instructions are also given in this article.
Best of luck!