URGENT!Windows Xp installation Problem..?

Hi,I have a 5 year old pentium 4 3.06 ghz computer which was working fine until today...out of a sudden a message that said that I needed to install windows xp again appeared...I had already installed it again(1 more time after the first time) and everything had gone fine:I just called a number and the operator told me what to do...this time is more complicated...while it asks me to do the installation,every time I go to accessories%26gt;windows installation(not sure if I spelled it correct-my windows are greek!) ,the installation does not start because it sais that a certain action unit or team(I don't know the actual word in english-sorry)is disabled..it also says that maybe it is disabled because of protection against viruses or security..I recently installed a wireless network adapter if that can help...I have windows xp 2002 sp2..please help it says I only have 3 days to istall windows again...help

URGENT!Windows Xp installation Problem..?virus scanner

1. try system restore to a point before the problem.

start menu -%26gt; programs -%26gt; accessories -%26gt; system tools -%26gt; system restore

See if this fixes the problem. if not you may have to do a full install.

Reformat and start from scratch. bear in mind that if you do this all your data will be wiped.

Back up everything you want to keep (documents, mp3's email addresses, emails, internet favourites.

get your xp cd.

put it in the drive

boot your machine

Your machine should boot to the installer.

Follow the prompts. You will need your xp key number.

IF your machine won't boot to the cd you will need to change your bios settings. to do this, hit 'delete' when the bios information shows just after the machine has switched on. Change your drive order so your cd is first in the sequence.

If you get stuck, msg me.