Error Message	Meaning of Error Message and What to Do
Bad Sector writing or reading to drive	Sector markings on the disk may be fading. Try ScanDisk or reformat the disk.
Bad command or file not found	The OS command just executed cannot be interpreted, or the OS cannot find the program file specified in the command line. Check the spelling of the filename and, for DOS or when working from a Windows startup disk, check that the path to the program file has been given to the OS.
Beeps during POST	Before the video is checked, during POST, the ROM BIOS communicates error messages with a series of beeps. Each BIOS manufacturer has its own beep codes, but the following are examples of some BIOS codes. For specific beep codes for your motherboard, see the Web site of the motherboard or BIOS manufacturer.
One single beep followed by three, four, or five beeps	Motherboard problems, possible with DMA, the COMOS setup chip, timer, or the system bus.
Two beeps	The POST numeric code is displayed on the monitor.
Two beeps followed by three, four, or five beeps	First 64K of RAM has errors
Three beeps followed by three, four, or five beeps	Keyboard controller has failed or video controller has failed
Four beeps followed by two, three, or four beeps	Problem with serial or parallel ports, system timer, or time of day
Continuous Beeps	Problem with power supply
Configuration/CMOS error	Setup information does not agree with the actual hardware the computer found during boot. May be caused by a bad or weak battery or by changing hardware without changing setup. Check setup for errors.
Insufficient memory	This error happens under Windows when too many applications are open. Close some applications. A reboot may help.
Hard drive not found	The OS cannot locate the hard drive, or the controller card is not responding.
Fixed disk error	The PC cannot find the hard drive that setup told it to expect. Check the cables, connections, power supply, and setup information.
Incorrect DOS version	When you execute a DOS external command, the OS looks for a program file with the same name as the command. It finds that this file belongs to a different version of the OS than the one that is now running. Use the Setver command in Autoexec.bat.
Invalid drive specification	The PC is unable to find a hard drive or a floppy drive that setup tells it to expect. Look for errors in setup, or for a corrupted partition table on the hard drive.
Invalid or missing the disk Command.com	This may be caused by a nonbooting disk in drive A. Remove the disk and boot from drive C. Command.com on drive C may have been erased, or the path could not be found.
No boot device available	The hard drive is not formatted, or the format is corrupted, and there is no disk in drive A. Boot form a floppy and examine your hard drive corruption.
Non-system disk or disk error	Command.com or one of two OS hidden files is missing from the disk in drive A or the hard drive. Remove the disk in drive A and boot from the hard drive. Use the SYS command to restore system files.
Not ready reading drive A: Abort, Retry, Fail?	The disk in drive A is missing, is not formatted, or is corrupted. Try another disk.
Numeric codes during POST Code in the 100 Range Code in the 200 Range Code in the 300 Range Code in the 500 Range Code in the 600 Range Code in the 700 Range Code in the 900 Range Code in the 1100-1200 Code in the 1300 Range Code in the 1700 Range Code in the 6000 Range Code in the 7300 Range	Sometimes numeric codes are used to communicate errors at POST. Some examples for IBM XT/AT error codes include. Motherboard errors RAM errors Keyboard errors Video controller errors Floppy drive errors Coprocessor errors Parallel port errors Async (communications adapter) errors Game controller or joystick errors Hard drive errors SCSI device or network card errors Floppy drive errors
Track 0 bad, disk not usable	This usually occurs when you attempt to format a floppy disk using the wrong format type. Check the disk type and compare it to the type specified in the format command.
Write-protect error writing drive A:	Let the computer write to the disk by setting the switch on a 3 ½-inch disk or removing the tape form a 5 ¼-inch disk.
Missing operating system error loading operating system	The MBR is unable to locate or read the OS boot sector on the active partition or there is a translation problem on large drives boot from a floppy and examine the hard drive file system for corruption.
Unknown error at POST	See the Web site of the system BIOS manufacturer: · AMI BIOS: www.ami.com · Award BIOS and Phoenix BIOS: www.phoenix.com · Compaq: www.compaq.com · Dell: www.dell.com · IBM: www.ibm.com
Error in Config.sys line xx	There is a problem loading a device driver or with the syntax of a command line. Check the command line for errors. Verify the driver files are in the right directory. Reinstall the driver files.
Himem.sys not loaded, missing or corrupt Himem.sys	Himem.sys is corrupted, not in the right directory, or not the right version for the currently loading OS. Verify Himem.sys
Device not found	Errors in System.ini, Win.ini, or the registry. Look for references to devices or attempts to load device drivers. Use Device Manager to delete a device or edit System.ini or Win.ini.