| 00 | No Error |
| 01 | Invalid function number |
| 02 | File not found |
| 03 | Path not found |
| 04 | Too many open files (no handles left) |
| 05 | Access denied |
| 06 | Invalid handle |
| 07 | Memory control blocks destroyed |
| 08 | Insufficient memory |
| 09 | Invalid memory block address |
| 0A | Invalid environment |
| 0B | Invalid format |
| 0C | Invalid access mode (open mode is invalid) |
| 0D | Invalid data |
| 0E | Reserved |
| 0F | Invalid drive specified |
| 10 | Attempt to remove current directory |
| 11 | Not same device |
| 12 | No more files |
| 13 | Attempt to write on a write-protected diskette |
| 14 | Unknown unit |
| 15 | Drive not ready |
| 16 | Unknown command |
| 17 | CRC error |
| 18 | Bad request structure length |
| 19 | Seek error |
| 1A | Unknown media type |
| 1B | Sector not found |
| 1C | Printer out of paper |
| 1D | Write fault |
| 1E | Read fault |
| 1F | General failure |
| 20 | Sharing violation |
| 21 | Lock violation |
| 22 | Invalid disk change |
| 23 | FCB unavailable |
| 24 | Sharing buffer overflow |
| 25 | Reserved |
| 26 | Unable to complete file operation (DOS 4.x) |
| 27-3 | 1 Reserved |
| 32 | Network request not supported |
| 33 | Remote computer not listening |
| 34 | Duplicate name on network |
| 35 | Network name not found |
| 36 | Network busy |
| 37 | Network device no longer exists |
| 38 | NetBIOS command limit exceeded |
| 39 | Network adapter error |
| 3A | Incorrect network response |
| 3B | Unexpected network error |
| 3C | Incompatible remote adapter |
| 3D | Print queue full |
| 3E | No space for print file |
| 3F | Print file deleted |
| 40 | Network name deleted |
| 41 | Access denied |
| 42 | Network device type incorrect |
| 43 | Network name not found |
| 44 | Network name limit exceeded |
| 45 | NetBIOS session limit exceeded |
| 46 | Temporarily paused |
| 47 | Network request not accepted |
| 48 | Print or disk redirection is paused |
| 49-4 | F Reserved |
| 50 | File already exists |
| 51 | Reserved |
| 52 | Cannot make directory entry |
| 53 | Fail on INT 24 |
| 54 | Too many redirections |
| 55 | Duplicate redirection |
| 56 | Invalid password |
| 57 | Invalid parameter |
| 58 | Network device fault |
| 59 | Function not supported by network (DOS 4.x) |
| 5A | Required system component not installed (DOS 4.x) |