I suggest to take it to a computer technician shop and pay the money to fix it
I suggest for the technician to partition the hard drive, copy your personal stuff to the new partition, then format the operating system and re install windows from your disk.
Here is more info, take a print of this and take it to the computer shop.
Partition the Hard drive – reasons
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Firstly C drive is compulsory for the Operating System (XP) (Vista), and you install all your programs on C drive.
D drive is made for YOUR files.
What you do is MOVE my documents to D drive.
When you download music, videos, pictures from your camera or make any MS Office documents or save emails, you save it on D drive.
The reason for this is to do with
1. Hard drive failure - usually a failed hard drive will not boot, but can often be seen when hooked up as a slave.
So when you get your new hard drive up and running, you can copy D drive from your old to your new. You haven’t lost anything.
2. Virus. Normally virus are programmed to infect C drive. If you get a bad virus all that has to be done is format the C drive partition then re install you OS and programs from disks.
You haven’t lost your personal stuff because its on D drive.
3. Scanning your C drive for virus or spyware. These malware programs live on C drive. It is not necessary to scan D drive. It is a lot quicker to scan a small partition than a large hard drive.
Now you can see the above is compromised by the fact that programs get updates and lots of programs are installed from the net. Therefore if you had to wipe out C drive it be hard to get it back to how it was.
To remedy this we use Norton Ghost to image C drive and store the Image on D drive.
(Vista requires a version 10 or newer of Ghost).
If you get a bad virus you just use the Ghost disk to boot up on, then copy the image stored on D drive back over C drive.
It takes less than 30 mins to rebuild C drive.
Also you may have this running on say a 250 gig HDD, and it fails. You buy a new 400 gig HDD and install both into you computer, the failed one as a slave.
Using the ghost disk to boot up on, you partition the 400 C drive to 30 gig (XP)and the remaining to D drive. Then you repack C drive from the image. Then Copy your old D drive files to your new one. In a time of less than 1 hour and it’s all running. The image loads all the drivers, OS everything.
Then you update new images of C drive every few months so that the one stored on D drive is not to far out of date.