Why is the Repair option not showing in Synology Storage Manager?

The Repair action in Storage Manager appears when Synology can rebuild a degraded pool onto a valid replacement drive. If it is greyed out or missing, work through these causes.

The replacement drive is too small

The new drive must be at least as large as the drive it replaces. A smaller drive cannot rebuild the pool, so Repair will not offer it. Check the exact capacities.

The drive is not recognised

Reseat the drive and confirm it shows as healthy in Storage Manager's HDD/SSD view. A drive that is not detected, or flagged with errors, cannot be selected for repair. On 2025 Synology models, also confirm your DSM version permits the drive (DSM 7.3 restored third-party HDD support).

The pool is crashed, not degraded

Repair only works on a degraded pool: one that lost redundancy but is still intact. If too many drives failed and the pool crashed, Repair is not available because there is no longer enough data to rebuild from; the path there is data recovery, not repair. Check whether Storage Manager says degraded or crashed.

The drive needs deactivating first

Sometimes a drive must be deactivated in Storage Manager before the pool will accept a replacement in that slot. Follow Synology's storage-pool repair steps in order. If Repair still will not appear on a genuinely degraded pool with a valid, recognised, large-enough CMR drive, contact Synology support before doing anything that writes to the pool.