Data recovery from external hard disk displaying the “Cyclic Redundancy Check” error message when connected to Windows

A Longford-based customer recently sent a 1TB Seagate Backup Plus disk for data recovery. When connected to a Windows PC, the following error message was displaying:

D:\ is not accessible
Data error (cyclic redundancy check)

Cyclic Redundancy Check is a mathematical equation used to ensure the integrity of data. It works by multiplying the number of bits in the data packet by a pre-determined number prior to data transmission and retains the answer. Once the data is received, it executes the same equation again. If the two answers match, your computer processor knows the data is intact. CRC checking is commonly used in TCP/IP networking but is also in disk-to-disk communication such as when an external hard disk or USB memory device is connected to a computer.
Fix Cyclical Redundancy Check errors
Typically, the Cyclic Redundancy Check error message tells us there is a problem with a storage device. In a small minority of cases, the issue can be resolved by running the Checkdisk (Chkdsk) command on the disk within Windows. However, in the vast majority of cases the Cyclic Redundancy Check error message is indicative of a more serious problem with a disk.

In this particular case the client’s Seagate Backup Plus disk had over 20,000 uncorrectiable bad sectors. We used our specialised data recovery equipment to “read around” these sectors and then performed a “read retry” operation on them. Our equipment does this at a very low level, meaning we can access data which would be otherwise unreadable to operating systems such as Windows, OS X or Linux.
We were successful in recovering all the file types needed by the client. These included .docx, .xlsx and .mdf (Microsoft Access) files. Case was closed with one extremely satisfied customer!

Drive Rescue Data Recovery Dublin offer a complete data recovery service for external hard disk drives such as Seagate Backup Plus, WD My Passport, MyPassport Ultra, Freecom Toughdrive, Maxtor M3, Toshiba Canvio, Transcend and Verbatim. To find out more visit: