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Logical disk errors describe problems reading data from a drive that is mechanically fully functional. Data recovery software addresses ways to retrieve data from drives with logical errors. NEARLY ALL DATA RECOVERY SOFTWARE is for drives with logical errors, not physical or mechanical errors and such software typically inappropriate from data recovery from physically damaged drives. In some cases, use of data recovery software may result in you losing data you could have retrieved by other means.A drive that has any kind of physical damage is far more difficult to recover data from. In many cases, a drive failure is cascading, typically beginning with subtle errors on the drive until increasing exponentially until the drive is a brick. Sometimes the subtle errors go unnoticed and by the time cascading failure becomes evident, it is too late to retrieve most of your data short of mechanical service.If a control chip on the board has failed, or there is another problem with the electronics on the board, sometimes that board can be replaced with an identical board, thus repairing the defect with the hard drive as a unit, and allowing full functionality including data access. This has been accomplished but is hit and miss largely due to undocumented differences in hard drive boards designated by the same model and series.== Low Temperature Data Retrieval ==Some hard drives respond to reduced temperature conditions, making them temporarily functional for the purpose of data retrieval. Engineers have placed drives in a freezer.