The purpose of above mentioned feature is to enhance the reading intensity for HDD which suffer from severe bad sectors by using special command, and also to improve working ability of magnet head via increased electricity.

However, as this function may expedite the degradation of HDD, it is not recommended to be used very often for normal cases. Meanwhile, we can casually use it for recovering some critical important file from damaged HDD and are able to get excellent effect.

Now, we would like to make a demo. We have a defective Hitachi drive on hand, according to customers information, there was a problem on magnet head and it can be detected by BIOS after head swap. However, the important data recovery hardware required cannot be recovered and hope we can help to resolve.

We well know that this is a big difficulty for us even experts to recover data from HDD after head swapped. The reason is that there will have severe bad sectors and head instability after this operation. By using traditional data recovery hardware tools, it first automatically scan and analyze all directory and data area once get to the first interface program. It is really timeconsuming,and also computer may crash or become unresponsive.

This problem can be essentially resolved by our latest updates of high level software DCEXP built in Data Compass. DCEXP adopts layered read operation, it access to root catalogue directly rather than data area. Once the directory been read out, users can recover their selected file(s). Under this circumstance, we do not need to spend time for scanning and it maximally saves time for recovering.

Now we start to recover the data from the HDD. First, connect HDD, DC and workstation computer properly and run the DC panel:

For drives that can be recognized normally, it is no need to set the parameters because SalvationDATA has provided the default setting. So generally you run the panel and after the drive is ready you can directly open the DC EXP. For multiple bad sector drives, you need to first run the ShadowDisk function and turn to ShadowDisk Control interface:

Shadow Disk that already connected well:

Please pay attention to:
1.The capacity of the Shadow Disk should be larger than the source drive.
2.For Shadow Disks, there should be no bad sectors.

After selecting the Shadow Disk, initialize and start up the Shadow Disk.

Thus, the control panel setting is finished and you need to open the DCEXP.

Directly open the ROOT in the partition, all the folders can be displayed normally and select the CWDATA folder that the client need, then the contents of the fold will be viewed inside the right side frame.

Select all the folders and prepare for the recovery:

So far, the total time consume, from Panel start to recovery, will lasts less than 3 minutes.

Data recovery being processed:

After a while, the recovery process finishes and you can view the files in the subfolders:

Till now, the files which the client needs are all recovered within 20 minutes. If you don t use DC for this kind of case which needs opening the drive and doing head swap before the imaging process, it will cost you several hours or even scores of hours based on the bad sector amount. For hard drives with large capacity, it will cost you even several days to finish the recovery process.

To ensure all data recovery rightly, we open those files by WINHEX. Unfortunately we found that one of the files (BB.DB) was not recovered success. All bits were 4040.

Compared with other files:

We got the same result even trying many times. It seems that there are serious bad sectors on the data position. But the customer required us that all the data of this file must be recovered. The only way is to use the Intensive Read function.

Turn to Shadow Disk Control page in DC PANEL, open Intensive Read function:

Back to DCEXP control page, read this file again:

In the recovery course, obvious different sound compared with normal recovery course, after a few minutes, data recover success:

Open this file by WINHEX again:

We found that this file could be opened and all bits were read success. Now, all requires data recovery finished.

We believe this case will be helpful for data recovery engineers.

Tip: if there is not only a little of data needed recover, don t use Intensive Read function at the beginning. Try to
recover as much as data which could be recovery directly, then open this function for the others.