diff --git a/weed/storage/volume_vacuum.go b/weed/storage/volume_vacuum.go
index be7f6891f..06de181b5 100644
--- a/weed/storage/volume_vacuum.go
+++ b/weed/storage/volume_vacuum.go
@@ -440,7 +440,7 @@ func copyDataBasedOnIndexFile(srcDatName, srcIdxName, dstDatName, datIdxName str
 		n := new(needle.Needle)
 		err := n.ReadData(srcDatBackend, offset.ToActualOffset(), size, version)
 		if err != nil {
-			return nil
+			return fmt.Errorf("cannot hydrate needle from file: %s", err)
 		}
 
 		if n.HasTtl() && now >= n.LastModified+uint64(sb.Ttl.Minutes()*60) {