diff --git a/chain/ring.go b/chain/ring.go
index acee086..06645b0 100644
--- a/chain/ring.go
+++ b/chain/ring.go
@@ -38,7 +38,7 @@ func (c *Chain) GetRingOutputs(amount uint64, offsets []uint64) ([]types.PublicK
 		case types.TxOutputBare:
 			toKey, ok := out.Target.(types.TxOutToKey)
 			if !ok {
-				return nil, fmt.Errorf("ring output %d: unsupported target type %T", i, out.Target)
+				return nil, coreerr.E("Chain.GetRingOutputs", fmt.Sprintf("ring output %d: unsupported target type %T", i, out.Target), nil)
 			}
 			pubs[i] = toKey.Key
 		default:
diff --git a/consensus/block.go b/consensus/block.go
index 5345b6f..dfaf16b 100644
--- a/consensus/block.go
+++ b/consensus/block.go
@@ -152,8 +152,8 @@ func expectedBlockMajorVersion(forks []config.HardFork, height uint64) uint8 {
 func checkBlockVersion(blk *types.Block, forks []config.HardFork, height uint64) error {
 	expected := expectedBlockMajorVersion(forks, height)
 	if blk.MajorVersion != expected {
-		return fmt.Errorf("%w: got %d, want %d at height %d",
-			ErrBlockMajorVersion, blk.MajorVersion, expected, height)
+		return coreerr.E("checkBlockVersion", fmt.Sprintf("got %d, want %d at height %d",
+			blk.MajorVersion, expected, height), ErrBlockMajorVersion)
 	}
 	return nil
 }
@@ -226,7 +226,7 @@ func IsPreHardforkFreeze(forks []config.HardFork, version uint8, height uint64)
 func ValidateTransactionInBlock(tx *types.Transaction, txBlob []byte, forks []config.HardFork, height uint64) error {
 	// Pre-hardfork freeze: reject non-coinbase transactions in the freeze window.
 	if !isCoinbase(tx) && IsPreHardforkFreeze(forks, config.HF5, height) {
-		return fmt.Errorf("%w: height %d is within HF5 freeze window", ErrPreHardforkFreeze, height)
+		return coreerr.E("ValidateTransactionInBlock", fmt.Sprintf("height %d is within HF5 freeze window", height), ErrPreHardforkFreeze)
 	}
 
 	return ValidateTransaction(tx, txBlob, forks, height)