uncorrectable

Uncorrectable is an adjective meaning unable to be corrected or remedied. In technical contexts, it describes errors or conditions that cannot be fixed by the available automatic correction methods and may require intervention or cessation of a process. The term is commonly used in data integrity, computer memory, and storage systems.

In memory and error correction codes, systems with ECC (error-correcting code) can typically correct single-bit errors and detect some multi-bit errors. A double-bit error is often detected but uncorrectable by the ECC scheme, which can trigger an error condition such as a machine check or a halt to prevent further corruption.

In storage devices, an uncorrectable read error (URE) occurs when a disk cannot be read correctly despite retries and error-correcting attempts. UREs can lead to data loss or degraded reliability in RAID configurations, depending on redundancy and recovery options. Modern drives and filesystems record uncorrectable errors as part of health monitoring and event logs.

In software and networking, an uncorrectable error or uncorrectable exception refers to a fault that cannot be recovered through normal error handling. Such conditions may terminate a program, trigger a crash, or require user or administrative intervention. In communications, errors that exceed the correcting capability of the chosen channel code are considered uncorrectable, leaving the received data unusable without external correction.

Etymology-wise, the term combines un- with correctable, signaling that automatic or routine correction is not possible given the current mechanism. Overall, uncorrectable conveys a state where automatic remediation is insufficient and further action is needed.