Error Codes

All the FCB functions report an error by returning 0FFh in the AL
register.  Other functions report an error by setting the carry flag
and placing an error code in the AX register.  DOS 2.x functions
return the error codes 0 - 12h.  Under DOS 3.x, it is best to call
function 59h to obtain more detailed error information.

Code  Meaning                           Code  Meaning
00h  No error                           22h  Invalid disk change
01h  Invalid function number            23h  FCB unavailable
02h  File not found                     24h  Sharing buffer overflow
03h  Path not found                     32h  Network request not supported
04h  No handle available                33h  Remote computer not listening
05h  Access denied                      34h  Duplicate name on network
06h  Invalid handle                     35h  Network name not found
07h  Memory control blocks destroyed    36h  Network busy
08h  Insufficient memory                37h  Network device no longer exists
09h  Invalid memory block address       38h  Net BIOS command limit exceeded
0Ah  Invalid environment                39h  Network adapter hardware error
0Bh  Invalid format                     3Ah  Incorrect response from network
0Ch  Invalid access code                3Bh  Unexpected network error
0Dh  Invalid data                       3Ch  Incompatible remote adapter
0Eh  Reserved                           3Dh  Print queue full
0Fh  Invalid drive specification        3Eh  Not enough space for print file
10h  Attempt to remove the current      3Fh  Print file was deleted
directory                          40h  Network name was deleted
11h  Not same device                    41h  Access denied
12h  No more files                      42h  Network device type incorrect
13h  Disk write-protected               43h  Network name not found
14h  Unknown unit                       44h  Network name limit exceeded
15h  Drive not ready                    45h  Net BIOS session limit exceeded
16h  Unknown command                    46h  Temporarily paused
17h  Disk data error (CRC)              47h  Network request not accepted
18h  Bad request structure length       48h  Print or disk redirection paused
19h  Seek error                         50h  File exists
1Ah  Unknown media type                 51h  Reserved
1Bh  Sector not found                   52h  Cannot make directory entry
1Ch  Printer out of paper               53h  Critical-error interrupt failure
1Dh  Write fault                        54h  Too many redirections
1Eh  Read fault                         55h  Duplicate redirection
1Fh  General failure                    56h  Invalid password
20h  File sharing violation             57h  Invalid parameter
21h  File locking violation             58h  Network device fault


The following information is returned by the DOS function 59h:

  Error class:

Code    Meaning
01h    Out of resource
02h    Temporary situation; try again later
03h    Authorization
04h    Internal error in system software
05h    Hardware failure
06h    System failure; serious failure of system software
07h    Application software error
08h    Item requested not found
09h    Bad format (e.g., unrecognizable disk)
0Ah    Item locked
0Bh    Media error (e.g., CRC error)
0Ch    Already exists
0Dh    Unknown

  Suggested action:

Code    Meaning
01h    Try again now.
02h    Try again (a few times) after a pause, then prompt user to
continue or abort.
03h    Ask user to correct input, then retry.
04h    Orderly abort; close files, then shut down the application.
05h    Immediate abort; don't even try to close files.
06h    Ignore.
07h    Ask user to do something (like insert appropriate disk), then

  Locus of error:

Code    Meaning
01h    Unknown
02h    Block device (e.g., disk drive)
03h    Network
04h    Serial device
05h    Memory

See also: 59h

DOS - Error codes