diff --git a/rai/core_test/block_store.cpp b/rai/core_test/block_store.cpp
index a5699c2d..7f2345c7 100644
--- a/rai/core_test/block_store.cpp
+++ b/rai/core_test/block_store.cpp
@@ -782,3 +782,72 @@ TEST (block_store, upgrade_v6_v7)
 	ASSERT_EQ (store.unchecked_end (), store.unchecked_begin (transaction));
 }
 
+// Databases need to be dropped in order to convert to dupsort compatible
+TEST (block_store, change_dupsort)
+{
+	auto path (rai::unique_path ());
+	bool init (false);
+	rai::block_store store (init, path);
+	rai::transaction transaction (store.environment, nullptr, true);
+	ASSERT_EQ (0, mdb_drop (transaction, store.unchecked, 1));
+	ASSERT_EQ (0, mdb_dbi_open (transaction, "unchecked", MDB_CREATE, &store.unchecked));
+	rai::send_block send1 (0, 0, 0, rai::test_genesis_key.prv, rai::test_genesis_key.pub, 0);
+	rai::send_block send2 (1, 0, 0, rai::test_genesis_key.prv, rai::test_genesis_key.pub, 0);
+	ASSERT_NE (send1.hash (), send2.hash ());
+	store.unchecked_put (transaction, send1.hash (), send1);
+	store.unchecked_put (transaction, send1.hash (), send2);
+	{
+		auto iterator1 (store.unchecked_begin (transaction));
+		++iterator1;
+		ASSERT_EQ (store.unchecked_end (), iterator1);
+	}
+	ASSERT_EQ (0, mdb_drop (transaction, store.unchecked, 0));
+	mdb_dbi_close (store.environment, store.unchecked);
+	ASSERT_EQ (0, mdb_dbi_open (transaction, "unchecked", MDB_CREATE | MDB_DUPSORT, &store.unchecked));
+	store.unchecked_put (transaction, send1.hash (), send1);
+	store.unchecked_put (transaction, send1.hash (), send2);
+	{
+		auto iterator1 (store.unchecked_begin (transaction));
+		++iterator1;
+		ASSERT_EQ (store.unchecked_end (), iterator1);
+	}
+	ASSERT_EQ (0, mdb_drop (transaction, store.unchecked, 1));
+	ASSERT_EQ (0, mdb_dbi_open (transaction, "unchecked", MDB_CREATE | MDB_DUPSORT, &store.unchecked));
+	store.unchecked_put (transaction, send1.hash (), send1);
+	store.unchecked_put (transaction, send1.hash (), send2);
+	{
+		auto iterator1 (store.unchecked_begin (transaction));
+		++iterator1;
+		ASSERT_NE (store.unchecked_end (), iterator1);
+		++iterator1;
+		ASSERT_EQ (store.unchecked_end (), iterator1);
+	}
+}
+
+TEST (block_store, upgrade_v7_v8)
+{
+	auto path (rai::unique_path ());
+	{
+		bool init (false);
+		rai::block_store store (init, path);
+		rai::transaction transaction (store.environment, nullptr, true);
+		ASSERT_EQ (0, mdb_drop (transaction, store.unchecked, 1));
+		ASSERT_EQ (0, mdb_dbi_open (transaction, "unchecked", MDB_CREATE, &store.unchecked));
+		store.version_put (transaction, 7);
+	}
+	bool init (false);
+	rai::block_store store (init, path);
+	ASSERT_FALSE (init);
+	rai::transaction transaction (store.environment, nullptr, true);
+	rai::send_block send1 (0, 0, 0, rai::test_genesis_key.prv, rai::test_genesis_key.pub, 0);
+	rai::send_block send2 (1, 0, 0, rai::test_genesis_key.prv, rai::test_genesis_key.pub, 0);
+	store.unchecked_put (transaction, send1.hash (), send1);
+	store.unchecked_put (transaction, send1.hash (), send2);
+	{
+		auto iterator1 (store.unchecked_begin (transaction));
+		++iterator1;
+		ASSERT_NE (store.unchecked_end (), iterator1);
+		++iterator1;
+		ASSERT_EQ (store.unchecked_end (), iterator1);
+	}
+}
diff --git a/rai/core_test/rpc.cpp b/rai/core_test/rpc.cpp
index df49cb48..fb3d2ce0 100644
--- a/rai/core_test/rpc.cpp
+++ b/rai/core_test/rpc.cpp
@@ -1331,7 +1331,7 @@ TEST (rpc, version)
     ASSERT_EQ (200, response1.status);
 	ASSERT_EQ ("1", response1.json.get <std::string> ("rpc_version"));
     ASSERT_EQ (200, response1.status);
-	ASSERT_EQ ("7", response1.json.get <std::string> ("store_version"));
+	ASSERT_EQ ("8", response1.json.get <std::string> ("store_version"));
 	ASSERT_EQ (boost::str (boost::format ("RaiBlocks %1%.%2%.%3%") % RAIBLOCKS_VERSION_MAJOR % RAIBLOCKS_VERSION_MINOR % RAIBLOCKS_VERSION_PATCH), response1.json.get <std::string> ("node_vendor"));
 	auto & headers (response1.resp.fields);
 	auto access_control (std::find_if (headers.begin (), headers.end (), [] (decltype (*headers.begin ()) & header_a) { return boost::iequals (header_a.first, "Access-Control-Allow-Origin"); }));
diff --git a/rai/secure.cpp b/rai/secure.cpp
index abada52a..556d9581 100644
--- a/rai/secure.cpp
+++ b/rai/secure.cpp
@@ -1599,6 +1599,8 @@ void rai::block_store::do_upgrades (MDB_txn * transaction_a)
 		case 6:
 			upgrade_v6_to_v7 (transaction_a);
 		case 7:
+			upgrade_v7_to_v8 (transaction_a);
+		case 8:
 			break;
 		default:
 		assert (false);
@@ -1774,6 +1776,13 @@ void rai::block_store::upgrade_v6_to_v7 (MDB_txn * transaction_a)
 	mdb_drop (transaction_a, unchecked, 0);
 }
 
+void rai::block_store::upgrade_v7_to_v8 (MDB_txn * transaction_a)
+{
+	version_put (transaction_a, 8);
+	mdb_drop (transaction_a, unchecked, 1);
+	mdb_dbi_open (transaction_a, "unchecked", MDB_CREATE | MDB_DUPSORT, &unchecked);
+}
+
 void rai::block_store::clear (MDB_dbi db_a)
 {
 	rai::transaction transaction (environment, nullptr, true);
diff --git a/rai/secure.hpp b/rai/secure.hpp
index c75bead7..4c4c558b 100644
--- a/rai/secure.hpp
+++ b/rai/secure.hpp
@@ -395,6 +395,7 @@ public:
 	void upgrade_v4_to_v5 (MDB_txn *);
 	void upgrade_v5_to_v6 (MDB_txn *);
 	void upgrade_v6_to_v7 (MDB_txn *);
+	void upgrade_v7_to_v8 (MDB_txn *);
 	
 	void clear (MDB_dbi);