| Previous | Next |
| ERROR_CANNOT_MAKE | ERROR_OUT_OF_STRUCTURES |
ERROR_FAIL_I24
What ERROR_FAIL_I24 means
ERROR_FAIL_I24 is a Win32 system result whose documented message is: “Fail on INT 24.” In practical troubleshooting, it belongs to legacy DOS critical-error handling and compatibility code that still surfaces through old utilities, installers, emulators, or translated device operations. The numeric result identifies the failed contract, while the operation and target object explain why this particular result appeared.
Typical causes
- a removable or block device reported a condition that the INT 24 handler could not resolve
- a compatibility layer mapped a low-level DOS critical error without a richer Win32 result
- an old application expected an interactive Abort, Retry, Ignore response that is unavailable in a service or unattended session
How to investigate the result
- identify the executable or compatibility component that originated the code
- capture the immediately preceding file or device request and its target path
- check storage, removable-media, and controller events at the same timestamp
When investigating this result, start with the first failing call rather than a later cleanup error. Preserve the raw it before any wrapper converts it. Record whether it is reproducible in a clean process, a new user session, or after the relevant object is recreated.
Developer guidance
Modern code should not build recovery around INT 24 semantics. Translate the failure at the compatibility boundary into a current storage or I/O error and retain the original value only as diagnostic evidence. Logs should include the operation name, canonical target, process architecture, operating-system build, and the state that was validated immediately before the call. Avoid blind retries while the same precondition remains unchanged.
Administrator and support guidance
Confirm whether the failing program is a legacy binary and whether it is accessing removable media, mapped drives, or redirected devices. Reproduce interactively before changing storage policy. Before restarting after this result, collect evidence because a restart may clear the state responsible for it. When a it workaround succeeds, record exactly which process, mapping, media, driver, or configuration value changed.
Example incident
A legacy maintenance utility reaches an unreadable sector on removable media, attempts its DOS critical-error path, and the host reports this result because no usable handler response is available. A useful incident timeline shows the successful setup steps, the first operation returning it, and any secondary errors produced during its rollback.
How it differs from related results
Unlike a normal read or write error, this value describes failure of the old critical-error path itself; the underlying media problem may be reported only in an earlier log entry. That distinction determines whether the remedy belongs in application input, resource release, mapping topology, driver compatibility, or underlying storage.
Evidence worth collecting
Capture evidence around the condition “a removable or block device reported a condition that the INT 24 handler could not resolve.” The result evidence package should include the exact API or command, all non-secret input fields, normalized paths or device names, object ownership, and a timestamp correlatable with Windows Event Log and application tracing. The first concrete it check should be to identify the executable or compatibility component that originated the code.
Recovery and verification
Recovery from it is complete only when the original operation succeeds under the same relevant conditions. After fixing it, repeat the action and verify that no stale mapping or handle remains. Run the operation a second time to confirm that the setup and cleanup associated with it are idempotent. If it disappears only after reboot, continue investigating the owner or leaked state rather than treating reboot as the permanent correction.
When to escalate
Escalate it with a minimal reproduction, the exact it value, application and component versions, target path or device class, and the collected state before and after this failure. For a legacy the case, also state whether the executable is 16-bit, DOS-derived, virtualized, redirected, or running under a compatibility subsystem.
References
Looking for a different code? Search another status or error code.