How to recover hard disk drive (HDD) with bad sectors
One of the possible reason of drive fail is bad sectors that appears on the drive surface. It may be physical or logical bad sector, which differs by nature. Physical bad sector is a cell of drive surface which can't be read by drive and makes the controller to access it over and over try to read successfully, while the SoftAmbulance product looks like hanged. Another type of bad sector, the logical problem, is similar to the physical by symptoms, but may be fixed with low-level format without remap. Our product uses standard Windows procedures to access the drive to make you sure we will not perform anything unexpected that can damage your drive and information, but in case of bad sectors this is not the best solution and may cause the product to hang.
If you can't complete the scan of the drive and you've already tried to enlarge your swap file to avoid running out of memory, you should try to find the bad sector and avoid the scan of it. You will need to use Partition Doctor in such cases.
Partition doctor provides the way to scan only part of the drive, so you can scan the part of the device before the bad sector and another one after it. Start the program, click Menu-Drives-Map Virtual Partition and you will be able to enter the starting and ending point of the partition in sectors count. To get the maximum sectors count on the drive, select the drive and click Max.
So how to use this feature? For example, if the scan stops near 40%, you need to map the first virtual partition for 0-40% of the drive sectors. The point is to leave the problem area behind the virtual partition.
Open the Map Virtual Partition menu, click Max, copy the max value to calculator and multiple by 0.4 (40%) to get 40% of the value, and copy it back to the Size in sectors field. Map this virtual partition and it will appear in the drive list as a drive available for scan, then just select and scan it. If the product will hang near the end of scanning, then you've included the bad sector in the virtual partition, and you have to correct it - map another virtual partition for 0-35% of drive surface.
Once you will be able to complete the scan, recover your files and start to map another virtual partition for the rest of drive surface. If your first partition was for 0-35%, map the second one for 40-100% of scanning. You will need to set the Max * 0.4 for starting value and Max * (1-0.4) which is Max * 0.6 for size in sectors. If this partition will make the product hand in the beginning of the scan, set the starting sector of partition as Max * 0.45 and size in sectors as Max * 0.55.
It's possible that you will need to slice your second virtual partition to another two virtual partitions if there will be another problem sector area in another place of the drive.
If you will have any difficulties with this technique ,please contact our support service with the screenshot of Map Virtual Partition window, don't forget to select the drive you need to scan and click to the Max to give us the sectors count of the drive on the screenshot.
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