diff --git a/src/bitcoin-tx.cpp b/src/bitcoin-tx.cpp
--- a/src/bitcoin-tx.cpp
+++ b/src/bitcoin-tx.cpp
@@ -627,7 +627,7 @@
 
         const int nOut = prevOut["vout"].get_int();
         if (nOut < 0) {
-            throw std::runtime_error("vout must be positive");
+            throw std::runtime_error("vout cannot be negative");
         }
 
         COutPoint out(txid, nOut);
diff --git a/src/rpc/avalanche.cpp b/src/rpc/avalanche.cpp
--- a/src/rpc/avalanche.cpp
+++ b/src/rpc/avalanche.cpp
@@ -279,7 +279,7 @@
         int nOut = find_value(stake, "vout").get_int();
         if (nOut < 0) {
             throw JSONRPCError(RPC_DESERIALIZATION_ERROR,
-                               "vout must be positive");
+                               "vout cannot be negative");
         }
 
         const int height = find_value(stake, "height").get_int();
diff --git a/src/rpc/rawtransaction_util.cpp b/src/rpc/rawtransaction_util.cpp
--- a/src/rpc/rawtransaction_util.cpp
+++ b/src/rpc/rawtransaction_util.cpp
@@ -71,7 +71,7 @@
         int nOutput = vout_v.get_int();
         if (nOutput < 0) {
             throw JSONRPCError(RPC_INVALID_PARAMETER,
-                               "Invalid parameter, vout must be positive");
+                               "Invalid parameter, vout cannot be negative");
         }
 
         uint32_t nSequence =
@@ -202,7 +202,7 @@
             int nOut = find_value(prevOut, "vout").get_int();
             if (nOut < 0) {
                 throw JSONRPCError(RPC_DESERIALIZATION_ERROR,
-                                   "vout must be positive");
+                                   "vout cannot be negative");
             }
 
             COutPoint out(txid, nOut);
diff --git a/src/wallet/rpcwallet.cpp b/src/wallet/rpcwallet.cpp
--- a/src/wallet/rpcwallet.cpp
+++ b/src/wallet/rpcwallet.cpp
@@ -2726,7 +2726,7 @@
                 if (nOutput < 0) {
                     throw JSONRPCError(
                         RPC_INVALID_PARAMETER,
-                        "Invalid parameter, vout must be positive");
+                        "Invalid parameter, vout cannot be negative");
                 }
 
                 const TxId txid(ParseHashO(o, "txid"));
diff --git a/test/functional/abc_rpc_buildavalancheproof.py b/test/functional/abc_rpc_buildavalancheproof.py
--- a/test/functional/abc_rpc_buildavalancheproof.py
+++ b/test/functional/abc_rpc_buildavalancheproof.py
@@ -55,7 +55,7 @@
         negative_vout = good_stake.copy()
         negative_vout['vout'] = -1
         check_buildavalancheproof_error(-22,
-                                        "vout must be positive",
+                                        "vout cannot be negative",
                                         [negative_vout],
                                         )
 
diff --git a/test/functional/rpc_rawtransaction.py b/test/functional/rpc_rawtransaction.py
--- a/test/functional/rpc_rawtransaction.py
+++ b/test/functional/rpc_rawtransaction.py
@@ -127,7 +127,7 @@
                                 self.nodes[0].createrawtransaction, [{'txid': txid}], {})
         assert_raises_rpc_error(-8, "Invalid parameter, vout must be a number",
                                 self.nodes[0].createrawtransaction, [{'txid': txid, 'vout': 'foo'}], {})
-        assert_raises_rpc_error(-8, "Invalid parameter, vout must be positive",
+        assert_raises_rpc_error(-8, "Invalid parameter, vout cannot be negative",
                                 self.nodes[0].createrawtransaction, [{'txid': txid, 'vout': -1}], {})
         assert_raises_rpc_error(-8, "Invalid parameter, sequence number is out of range",
                                 self.nodes[0].createrawtransaction, [{'txid': txid, 'vout': 0, 'sequence': -1}], {})
@@ -551,7 +551,7 @@
 
         inputs[0]['vout'] = -1
         assert_raises_rpc_error(
-            -8, 'Invalid parameter, vout must be positive',
+            -8, 'Invalid parameter, vout cannot be negative',
             self.nodes[0].createrawtransaction, inputs, outputs)
 
         inputs[0]['vout'] = 1