diff --git a/src/init.cpp b/src/init.cpp
index 71971a76427..b57a207e90e 100644
--- a/src/init.cpp
+++ b/src/init.cpp
@@ -380,7 +380,7 @@ std::string HelpMessage(HelpMessageMode mode)
     strUsage += HelpMessageOpt("-port=<port>", strprintf(_("Listen for connections on <port> (default: %u or testnet: %u)"), Params(CBaseChainParams::MAIN).GetDefaultPort(), Params(CBaseChainParams::TESTNET).GetDefaultPort()));
     strUsage += HelpMessageOpt("-proxy=<ip:port>", _("Connect through SOCKS5 proxy"));
     strUsage += HelpMessageOpt("-proxyrandomize", strprintf(_("Randomize credentials for every proxy connection. This enables Tor stream isolation (default: %u)"), DEFAULT_PROXYRANDOMIZE));
-    strUsage += HelpMessageOpt("-rpcserialversion", strprintf(_("Sets the serialization of raw transaction or block hex returned in non-verbose mode, non-segwit(0) or segwit(>0) (default: %d)"), DEFAULT_RPC_SERIALIZE_VERSION));
+    strUsage += HelpMessageOpt("-rpcserialversion", strprintf(_("Sets the serialization of raw transaction or block hex returned in non-verbose mode, non-segwit(0) or segwit(1) (default: %d)"), DEFAULT_RPC_SERIALIZE_VERSION));
     strUsage += HelpMessageOpt("-seednode=<ip>", _("Connect to a node to retrieve peer addresses, and disconnect"));
     strUsage += HelpMessageOpt("-timeout=<n>", strprintf(_("Specify connection timeout in milliseconds (minimum: 1, default: %d)"), DEFAULT_CONNECT_TIMEOUT));
     strUsage += HelpMessageOpt("-torcontrol=<ip>:<port>", strprintf(_("Tor control port to use if onion listening enabled (default: %s)"), DEFAULT_TOR_CONTROL));
@@ -988,6 +988,9 @@ bool AppInitParameterInteraction()
     if (GetArg("-rpcserialversion", DEFAULT_RPC_SERIALIZE_VERSION) < 0)
         return InitError("rpcserialversion must be non-negative.");
 
+    if (GetArg("-rpcserialversion", DEFAULT_RPC_SERIALIZE_VERSION) > 1)
+        return InitError("unknown rpcserialversion requested.");
+
     nMaxTipAge = GetArg("-maxtipage", DEFAULT_MAX_TIP_AGE);
 
     fEnableReplacement = GetBoolArg("-mempoolreplacement", DEFAULT_ENABLE_REPLACEMENT);