# X_STORAGE_WRITE_OUTCOME_UNKNOWN

## Means

a write was sent and its answer lost, and the disk could not say whether it landed

## Typical cause

the connection died after the last request of a write was sent and before the provider answered, and neither a stat of the key nor an abort of the upload could settle whether the object is the one sent

## Fix

`await disk.stat(key)` — the size and etag now at the key; the same as what was sent means it landed

[Storage](/error-codes#storage)