The damage that makes the disk unreadable can be divided in principle into two types. This may be mechanical damage (scratch) or media failure. In case of mechanical damage, professional data recovery service at https://www.salvagedata.com/hard-drive-recovery/ is essential.
Even if your hard disk has gone through hell - flood, fire flame or fifth-floor fall, it's still possible that the plates are undamaged and can be read in specialized laboratories. But you need to pay for it and their success rate approaching 100% is hope for all losers.
Until you call them, they will definitely advise you not to try to fix your hard drive yourself. Believe there is not so much mistrust in your golden hands as a year of experience.
However, the user's lack of working with the computer may confuse the situation even with the eventual resolution of problems. There are rarely situations when the user does not even know what he actually did with the system, or he is reluctant to provide information about the activity leading to the crash, in fear of a possible sanction.
Beware of repair programs
In the first place, the consumer must understand what he is doing. In any case, when it comes to the correction program, it is necessary to create an Undo disc. Repair programs always offer the creation of a disk that makes it impossible for the repair to return to its original state. The data recovery cost can increase in case somebody has been trying to fix, and the data on the disk has been rewritten and transferred.
If a problem occurs when reading from a hard disk, then programs such as ScanDisc or Norton Disk Doctor that are already mentioned should be used very carefully, it is better to have a professional firmware disk at this time. For non-risky data, then these programs can be used. For risky or sensitive data recovery, look for professionals at https://www.salvagedata.com/apple-mac-recovery/.
Under no circumstances, we recommend to not make any change to the FAT table because this is a case that is very difficult to repair. By contrast, saving data from a preformatted disk is no bigger problem. We also do not recommend Master-Slave to use multiple drives because it is not very safe.
