diff --git a/cmd/geth/snapshot.go b/cmd/geth/snapshot.go
index 20920a0f94..c00334ee9e 100644
--- a/cmd/geth/snapshot.go
+++ b/cmd/geth/snapshot.go
@@ -278,7 +278,8 @@ func pruneBlock(ctx *cli.Context) error {
 	var newAncientPath string
 	oldAncientPath := ctx.GlobalString(utils.AncientFlag.Name)
 	if !filepath.IsAbs(oldAncientPath) {
-		oldAncientPath = stack.ResolvePath(oldAncientPath)
+		// force absolute paths, which often fail due to the splicing of relative paths
+		return errors.New("datadir.ancient not abs path")
 	}
 
 	path, _ := filepath.Split(oldAncientPath)
diff --git a/core/headerchain.go b/core/headerchain.go
index fe4770a469..3e50c1eb07 100644
--- a/core/headerchain.go
+++ b/core/headerchain.go
@@ -250,6 +250,9 @@ func (hc *HeaderChain) writeHeaders(headers []*types.Header) (result *headerWrit
 				headHeader = hc.GetHeader(headHash, headNumber)
 			)
 			for rawdb.ReadCanonicalHash(hc.chainDb, headNumber) != headHash {
+				if frozen, _ := hc.chainDb.Ancients(); frozen == headNumber {
+					break
+				}
 				rawdb.WriteCanonicalHash(markerBatch, headHash, headNumber)
 				headHash = headHeader.ParentHash
 				headNumber = headHeader.Number.Uint64() - 1
diff --git a/core/rawdb/chain_iterator.go b/core/rawdb/chain_iterator.go
index 22d5188e91..883e17b782 100644
--- a/core/rawdb/chain_iterator.go
+++ b/core/rawdb/chain_iterator.go
@@ -95,7 +95,10 @@ func iterateTransactions(db ethdb.Database, from uint64, to uint64, reverse bool
 		number uint64
 		rlp    rlp.RawValue
 	}
-	if to == from {
+	if offset := db.AncientOffSet(); offset > from {
+		from = offset
+	}
+	if to <= from {
 		return nil
 	}
 	threads := to - from
diff --git a/eth/state_accessor.go b/eth/state_accessor.go
index 24a0e776f6..156e3f1daf 100644
--- a/eth/state_accessor.go
+++ b/eth/state_accessor.go
@@ -74,6 +74,9 @@ func (eth *Ethereum) stateAtBlock(block *types.Block, reexec uint64, base *state
 		// The optional base statedb is given, mark the start point as parent block
 		statedb, database, report = base, base.Database(), false
 		current = eth.blockchain.GetBlock(block.ParentHash(), block.NumberU64()-1)
+		if current == nil {
+			return nil, fmt.Errorf("missing parent block %v %d", block.ParentHash(), block.NumberU64()-1)
+		}
 	} else {
 		// Otherwise try to reexec blocks until we find a state or reach our limit
 		current = block
diff --git a/internal/ethapi/api.go b/internal/ethapi/api.go
index 091e9e7e82..7a3f0ad8bd 100644
--- a/internal/ethapi/api.go
+++ b/internal/ethapi/api.go
@@ -1774,10 +1774,16 @@ func (s *PublicTransactionPoolAPI) GetTransactionReceiptsByBlockNumber(ctx conte
 	if err != nil {
 		return nil, err
 	}
+	if receipts == nil {
+		return nil, fmt.Errorf("block %d receipts not found", blockNumber)
+	}
 	block, err := s.b.BlockByHash(ctx, blockHash)
 	if err != nil {
 		return nil, err
 	}
+	if block == nil {
+		return nil, fmt.Errorf("block %d not found", blockNumber)
+	}
 	txs := block.Transactions()
 	if len(txs) != len(receipts) {
 		return nil, fmt.Errorf("txs length doesn't equal to receipts' length")