Hi!! hoping someone can help me!!!! I have recently developed a Trojan on my pc, as i dont really know a lot about this i called in a friend who said that this Trogan had wreaked my hard drive, so we went and brought the same but new hard drive, installed it and tried reinstalling windows XP, but during installation a message pops up saying no hard drive is installed!! Please help me!!!!

Welcome to D-A-L.

Don't throw out your old hard disk just yet. It's possible that it's salvageable.

Check all your connections (power and data cables) and drive jumpers as applicable.

If your hard disk is an (E)IDE type this may help;
http://www.easeus.com/disk-copy/Sing...-Jumpering.htm
http://www.easeus.com/resource/insta...hard-drive.htm

If your hard disk is a SATA type;
http://www.easeus.com/resource/insta...hard-drive.htm

SCSI type;
http://www.easeus.com/resource/insta...hard-drive.htm

Post back with your progress and any further questions.

Often when a trojan "wrecks" a hard drive, it doesnt actually break it - it just corrupts it. It's worth trying to reformat your old drive, and trying to repair the boot sectors.
Also, with yuor new one, jumpers are very important. A jumper is that little plastic thing bridging 2 pins. Usually there are 3 positions for this to be in. Master, Slave or Cable Select. Master is for when you have one hd on its own, slave is if the hd is like a secondary hd (for data etc not os) and cable select is when you let the cable and mobo choose - so connecting the cable with master on it, it will use the hd as master.

Penguin Paul... Thankyou so much for your advice. As you may already have noticed i havn`t got a clue when it comes to all this technical stuff, My friend took my pc away with him, so i have phoned him with your advice, just got a call back saying that he has cracked my old hard drive, the jumpers was on cable select, by putting it on master they are able to get all my photos which i am so pleased about as i never backed anything up... So just need to sort the new hard drive out now, thats if its even needed. I will keep you posted, Thanks again!!!