(updated 12/16/2012)

What to do if your PC won't boot to your hard drive...

Note : this situation often ends in data loss, so pay attention and be very careful with what you attempt. If you are unsure, have someone with more experience try these things.

Note : there is absolutely no warranty against data loss.

Enter the BIOS of the PC and make sure that the C: drive is set to be the primary boot device. PCs from a few years back could boot to either the floppy (A:) drive or the hard (C:) drive. The PC was happy with either, or a "try one first then the other" scenario. Viruses came along, and it was no longer advisable to allow the floppy to be a boot device option - either on purpose or by accident. (Viruses found accidentally on a non-system floppy in the A: drive when a PC was booted would transfer themselves to the PC's hard drive to cause whatever damage they would cause.) Booting to the hard drive became the default, but could be changed. Modern PCs can also be made to boot to many other devices - including CDROMs, ZIP drives, and networks. The PC cannot know what is best and correct this for your PC. You must know, and you must declare it - by making, and saving, the appropriate selection in the BIOS.

Enter the BIOS of the PC and make sure that the C: drive can be seen in its true and full size. If it does not show up readily, use whatever utility there is within the BIOS to "find" the hard drive. Take whatever action to save the findings, and restart the computer. If the drive wasn't showing up - but now is - your computer should start normally again.

Note : if given a choice of hard drive sizes or layouts (i.e. Normal with such-and-such layout and x amount of space, or LBA with such-and-such layout and x amount of space), and you do not know which one to pick, pick the one that the BIOS itself indicates as being the correct choice. If the drive still won't boot after this and you chose LBA, choose Normal instead and try again. The problem may go away.

If the hard drive gets found, and your computer resumes normal operation - then this happens again after the PC has been off for a while, you probably need a new motherboard battery. The PC is "forgetting" the CMOS information it is supposed to retain when powered down.


If the drive can be "found" by the BIOS, but the PC fails to boot properly, it could be missing operating system files, or it could be missing partition or format information.

If it's just Windows that won't work, Windows can be fixed or reinstalled.

To see what you are missing, boot to a system disk (a floppy disk with the same operating system on it that the hard drive has). Try accessing the C: drive from the A: prompt. Explore subdirectories to see what's there, and try "typing" some files to see if they can be read properly.

Note : some drives are set up using non-Windows drive managing software. In the installation process, special boot diskettes should have been created to permit such a PC to gain access to the hard drive via the floppy drive. Trying to access a drive set up this way from a Windows system diskette will not work, or may yield strange results. If this is the case in your situation, you will need those special boot diskettes to see the hard drive correctly. If you don't know how the drive was set up, and you are prepared for data loss, then proceed on the assumption that the drive was set up without such software.

If you can see the drive, and you can see files, but the drive doesn't boot, the system files may be corrupt or absent. Use the SYS utility to copy these files onto the hard drive. Since these files occupy a specific location on a drive, they can safely be copied this way without overwriting any data or disrupting what's on the drive already. The PC may now work correctly again.

If you can see the drive, but you can't see files, or if exploring found files causes errors, the FAT table may be corrupt, and you are likely to lose data the more you explore. Consider your position - have you got your data backed up? Do you care if you lose your data? If there is something on the PC that you would like to get off it, can this be done - i.e. can the critical files be found, how big are they, can they be copied onto a floppy? If you really need your data, and you can afford it, go to a data recovery center to see what they can do for you. If you want to risk trying to get some data off the PC, go ahead. If you don't care, re-partition the drive, re-format it, and reinstall the operating system. If errors crop up during this restoration process, the drive is probably bad, and you should consider replacing it.

If you can't see the drive at all, (but the BIOS sees it) run the FDISK utility and look to see what the hard drive is set up like. If FDISK can see nothing, you may be able to re-partition the drive and format it again. This will cause total data loss, so proceed only when all other avenues of data recovery have been travelled. Since the drive had failed in the first place, this may not be possible - the drive may be bad. Lastly, you can try FDISK /MBR from an A: drive boot. This is supposed to restore the backup of the Master Boot Record from its isolated place on the drive, and may fix the situation.

Note : if you get errors during recovery and reinstallation of a suspected bad drive (bad sectors reported, program interruptions, etc.), forget it. Replace the drive.


If the drive cannot be "found" by the BIOS, you will never get the drive to boot. Proceed with the following :

With the power off, open the computer case and check the cabling inside - all connections for power and data transfer must be secure - restore power and have the BIOS look for the drive again.

If nothing still, the drive is probably bad. You can check this conclusion by installing an alternative drive known to be working correctly in the troubled PC to see if the BIOS can see it. If the alternative drive can be seen correctly, you can be fairly certain that the original drive is bad or dead. If the alternative drive cannot be seen correctly either, the problem lies elsewhere.

You can also check the suspected bad drive by putting it into a PC that is known to be working correctly. If this second PC cannot see the drive, then the drive is probably bad.


If the hard drive is bad, and it is still under warranty (typically three years with the drive's manufacturer) you can begin the process of returning the drive for service or exchange. You will need your bill of sale and information from the drive, including : brand (Fujitsu, Seagate, Maxtor, etc.), model, serial number, and date of manufacture. Contact the manufacturer by phone or email and arrange to return the drive to them. Manufacturer's track and authorize these returns with RMA reference numbers. Keep records of all contact with the manufacturer during this process.

Recent examples of RMA procedure (which may make you think about which brand you buy) :

Maxtor - required the drive be shipped prepaid to their offices in California. A replacement drive was sent out from their manufacturing plant in Malaysia. Process took two weeks.

Fujitsu - walked into Fujitsu depot in Mississauga, Ontario (on Matheson East, near Renforth) with drive, walked out in ten minutes with a replacement drive.

Drives are often replaced with newer, larger drives due to issues with availability. The Fuitsu drive mentioned above was replaced with a faster one of double the capacity. The warranty on the replacement runs only until the warranty on the replaced drive would have expired.

No manufacturer warrants against data loss. If there is information on the drive that you desperately need back, do not take your drive back to the manufacturer - take it to a data recovery center. The cost of retrieving data (when it's possible) is extremely high, so better hope that you don't have to do this.

If the hard drive is bad, and is out of warranty, you'll need to buy and install a new drive.


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