The worst thing that can happen to a computer user is the loss of his personal data. You can learn about methods of saving lost information on many computer and not only forums.
However, not all so simple. It should be remembered that in the most difficult cases, you should still trust professionals, and not such delusions and myths.
For external hard drives, it is best to use shock-resistant enclosures. Today marketing invites us to purchase hard drives in special rubberized cases. However, this is just a trick, they do not protect from falling in the end. Of course, hard drives look reliable, impressive and beautiful in such a case, instilling confidence in the safety of data. It is not surprising that such products are purchased by the customer. But only this "protection" does not particularly reduce the load on the parts of the disc during an impact or fall. In case of a fall from a small height, the rubberized case can really help, and even then, if the device is turned off. For 2.5-inch drives the allowable limit is half a meter, and for 3.5-inch drives it is only 20 cm. If the hard drive still worked during the fall, then it will most likely break. The fact is that the maximum allowable overloads on such a working device are 5-7 times lower than on a switched off one. Experts specifically tested several hard drives for drops. The height of 15 cm was fatal for everyone. A slightly better indicator, at 40 cm, was shown only by a device in which there were rubber dampers between the body and the disc itself. So shockproof cases don't really help in a really critical case.
If the hard drive is jolting, tap it with a metal object while booting. Let's be honest, for the full effect, only hitting the floor is not enough. But can such measures really fix the disc? The result will most likely be small particles that have broken off inside the body. They will begin to scratch the surface of the disk, and then it will be extremely difficult to recover data. Data can be destroyed especially well if, after turning on the device, drop it from a height of one meter. Beautiful cuts will appear on the surface of the pancakes, after which the information will be definitely lost. So the first signs of poor disk performance should be a reason for emergency data backup and a trip to data recovery specialists, and not attempts to wake up the device by hitting the case.
There is a vacuum inside the hard drive. Some customers believe there is either a vacuum or some inert gas inside the hard drives. That is why, when the hard drive is opened, air with dust is sucked into it. This myth is even somewhat useful, as it scares off some people who want to fix a hard drive at home by disassembling it. In fact, the inside of this device contains ordinary air, devoid of dust. Such sterility is needed so that nothing gets into the space between the disc and the head. At the dawn of their appearance, the disks were really absolutely sealed, they were even thrown into water, and after wiping the electronics board, they could be used further. After all, water did not get inside such devices. Modern discs have holes in the HDA casing or on the cover. Modern devices have holes in their casing with warning labels. Air filters are located there, which do not allow particles hazardous to the surface to pass through. Such changes were introduced by manufacturers in order to move to new technologies and reduce the cost of production. So do not immerse modern hard drives in water, the liquid will get inside the HDA through the filter.
A sterile repair room can also be provided at home. People think they can fix a hard drive at home too. You just need to clean the room beforehand and you can already do the assembly and disassembly of hard drives in it. This is one of the most popular misconceptions in data recovery. In fact, even an experienced professional needs a comfortable table, chair, tweezers, tripods, screwdrivers, and other equipment. Providing such a workplace, say, in the bathroom will not work, primarily for financial reasons. But people are trying to fix their device at home in order to save money. The disc must be disassembled and reassembled in a dust-free space. In this case, the repairman must wear special clothing. That is why it will not be possible to provide ideal conditions at home.
If the hard drive is not detected by the BIOS or operating system, there is nothing to do but disassemble it. If the software does not see the device, then you can use specialized hardware that can diagnose the hard drive. Even at this level, it is possible to identify bad sectors, replace the firmware of the device itself, even try to write off information from damaged areas and transfer it to another medium. And it is necessary to disassemble the disk only when it is physically faulty.
For a hard drive to work better, you need to cool or heat it. The hard drive has a servo drive that helps to better align the head with respect to the surface. A certain gap must be maintained between the head and the disc itself. Periodically, the head starts to malfunction. Someone came up with the idea that if you naturally heat or cool a disk and thereby cause expansion or contraction processes, then this could solve the problem. In fact, freezing the hard drive will lead to condensation between its platters. Turning on the device for the first time after it has cooled down may permanently damage it.
There is a special device for data recovery. Human fantasy gave rise to the myth of a miraculous device that recovers information directly from damaged hard drives. They say that magnets are installed inside it, as a result of which the chaotically scattered information is arranged in the right way. In fact, engineers solve data recovery problems either with software or special devices for working with hard drives. A "clean room" can also be used if disassembly is required. But no one ever restores data to a physically faulty disk; a donor device is used for this.
Special utilities solve the problem of data recovery. This myth claims that no specialists in this area are needed, since everything can be settled using special programs. However, even the most advanced utilities will not help in case of physical damage to the disk. In this case, you will have to restore to a healthy partition, or even better - to a new medium.
A broken disc can be repaired. Indeed, you can change the device firmware, identify and hide bad sectors. However, this does not imply device recovery. If you want to keep your data, you will have to use a new disk. That is why, when contacting data recovery specialists, a donor will most often be used - such a working hard drive, to which data will be restored. If someone promises to revive a deceased disk, then the technologies described in this section will most likely be used. However, the disk will not be repaired or new, and further work with it will be fraught with data risk. If the device starts to "crumble", then its operating time is coming to an end.
You can take a pancake from a non-working disk, insert it instead of a similar one in a working device and read all the data. For such a trick to happen, you need to guess the hard disk firmware and its series. Replacement should be done in completely similar devices. But even this does not negate the principles of working in a specially prepared room (remember about the "clean room") and the availability of the necessary equipment.
Professional restoration is too expensive, prices for work start at $ 800. There are people who benefit from spreading such a belief. In fact, the price is formed taking into account several factors. The complexity of data recovery, and hence the cost of work, directly depends on what the user did with the disk after its failure. That is why it is best to immediately turn off the computer and deny yourself the "pleasure" of dealing with the hard drive at home. Do not use untested utilities and disassemble the device, then the master will most likely be able to do without a "clean room". But this is the most extreme and expensive option. If the hard drive is physically sound, the cost of restoring information from it fluctuates around 1,500 rubles. Diagnostics is usually carried out free of charge, in case of an unsuccessful attempt to save data from the client, they should not take any payment.
Solid state drives are impossible to kill. Indeed, this type of drive does not have moving parts like a hard drive. It would seem that since there is nothing to spin, there is nothing to break. But this does not mean that such devices can be thrown and hit at them. Manufacturers tried to make such drives smaller and larger, forgetting about reliability. And an ordinary fall or hit in the aquatic environment will be as fatal for solid-state drives as for hard drives. So you should treat them carefully and hope for a little luck. It is worth remembering that such devices are also more expensive, but the number of write cycles for them is limited. Over time, SSDs slow down their speed.
The manufacturer guarantees 500 thousand hours of device operation, so you don't have to worry about the reliability of the device. These warranties require the device to last more than 50 years. However, statistics say that 4% of hard drives break in the first year of their work. The same time as indicated on the packaging indicates the estimated lifespan of such a model. But nowhere is it said that he should work that much. So these numbers have to do with marketing, not the reality.
It is better to pay more for recovery, then the data will be better restored. It should be understood that data cannot be recovered better or worse. This work will be done or not. To perform it, you will need specialized software, special devices, tools, and possibly a "clean room". By itself, this equipment is quite expensive, but the analogues do not differ enough to form a significant difference in the price of the service. In this case, we are talking about PR and unfair advertising.
Even after a complete overwrite, the data can be recovered due to remanence. This myth came to us from the past, when computers were huge and hard drives were small. Drives up to 1 megabyte were written byte byte, that is, one byte was placed in one cluster. In this case, it was really possible to look for residual magnetization and recover some data. Currently, data is written sector-by-sector, each containing 512 bytes. The density of the recording per square centimeter is gigabytes. So it is no longer necessary to talk about residual magnetization.