A hard disk cluster is the group of sectors and the smallest unit to hold a file. The size of a cluster depends upon the size of the volume or drive and is meant to enhance the storage efficiency. FAT, exFAT, NTFS, NTFS5 etc. use a definite cluster size to manage the data in the hard drive and the partitions are defined in terms of clusters at the time of formatting of the disk.
The cluster size can be maintained or modified using a third party tool. But, the process may cause serious corruption to the file system so, it is always advisable to have a proper backup of all your files. Even if you face any problem and unable to recover your data , you can use hard drive recovery software to recover data.
Suppose, after modifying the cluster size , the booting process halted in the middle and you tend to receive an error message , making all your data inaccessible. The following error message could be displayed.
“A Disk read error occurred. Press Ctrl-Alt-Del to restart”
Cause:
The above error message appears because of a possible corruption to the Master Boot Record or MBR.
Note: MBR is the boot sector or the first sector of a partitioned storage media. Moreover, MBR is responsible for recognizing the partitions and loading of the operating system.
Resolution:
In order to resolve the above error, you need to boot your system with the Windows installation CD or DVD. Thereafter, at the command prompt, run the command 'fixmbr to repair the MBR.
However, if 'fixmbr' command fails to repair the MBR, you have to reformat the hard disk and make a fresh installation of the operating system. Formatting erases the whole data from the hard drive and you have to restore the data from the backup. In case, backup is not available or failed to restore back the data, only any Windows hard drive recovery software can help you recover your data.
