What does Windows error code 704 (ERROR_FT_READ_RECOVERY_FROM_BACKUP) mean?

ERROR_FT_READ_RECOVERY_FROM_BACKUP

What ERROR_FT_READ_RECOVERY_FROM_BACKUP means

A fault-tolerant volume satisfied a read from a redundant copy after the primary location failed. In practical terms, this status belongs to redundant storage recovery: the file system successfully returns data but reports that it used backup redundancy because a member or sector failed.

Typical causes

• A disk member produced an unreadable area
• The storage layer could not remap a failing region
• A mirrored or redundant volume recovered the requested block

How to investigate

1. Inspect System event logs and storage health immediately
2. Identify the affected volume, physical member, and failing logical block
3. Run vendor diagnostics and verify backup freshness before further degradation

Developer guidance

The read succeeded, but the event is an early warning of storage failure. Repeated recovery should trigger maintenance rather than being hidden by application retries.

References

• Microsoft: System error codes 500–999