If the MBR is all right, verify the DBR (DOS Boot Record). As we have already discussed, this is the first sector in the DOS partition and contains a small program that loads the hidden files and boots the operating system.
The DBR also contains much important information about the FAT, root directory clusters and size of the partition etc. Use some Diskedit like utility to read the DBR information if the DBR is corrupted or has some illegal information restore the DBR from the Backup.
You can also rewrite the DBR of the partition with the help of Diskedit by providing appropriate information.
There is also a very easy way to find out the area of corruption. The error messages which are displayed on the screen have some specific cause to be displayed. The description of some important error messages is as follows:
Message |
Description |
“Sector not found reading drive” |
This message can appear during any DOS operation. Generally, it is caused either by fading or the loss of a sector ID. |
“Data error reading drive” |
This message can appear during any DOS operation. It is caused by failing the data check – CRC (Cyclic Redundancy Check) or ECC (Error Correction Code). This “Data check” refers to the mechanism used to check whether the data read from the disk is reliable. |
“ 0 hard disk(s) found" |
It is displayed if the hard disk is not detected by the BIOS of the computer. Check the power and data cable connections of the hard disk. If connections are all right, the problem may be due to some hardware error of hard disk. |
“Hard Drive failure, press F1 to continue” |
Same as above |
“Invalid drive specification” |
It is displayed in the condition when either the system does not recognize the hardware, or there is no partition information, or the device driver of the drive is missing. |
“Invalid configuration press F1 to continue” |
If the hard disk is available, Either the battery in the motherboard is dead, and the system has lost its configuration SETUP information or the disk is not responding. |
“Invalid partition table” |
This is the MBR error message. It is displayed when the partition table of the MBR does not have the valid partition information. |
“Error loading operating system” |
This is the MBR error message. It is displayed due to any type of MBR information corruption. |
“Missing operating system” |
Same as above. |
“Disk boot failure” |
It is the DBR error message. Normally, The Hard drive should be accessible if you boot from the floppy. Though it is not bootable but that should not affect the access to the data of the drive. |
“non system disk or disk error” |
Same as above. |
“Bad or missing command interpreter” |
This message is displayed due to Bad or Missing Command Interpreter. For example if the operating do not find the command.com in current path or the command.com is corrupted. |
