diff -Nrup a/src/jsonrpccpp/server/connectors/httpserver.cpp b/src/jsonrpccpp/server/connectors/httpserver.cpp

--- a/src/jsonrpccpp/server/connectors/httpserver.cpp	2020-01-13 22:48:30.000000000 +0100

+++ b/src/jsonrpccpp/server/connectors/httpserver.cpp	2020-07-26 18:42:23.148244386 +0200

@@ -14,6 +14,10 @@

 #include <jsonrpccpp/common/specificationparser.h>

 #include <sstream>

+#if MHD_VERSION < 0x00097002

+typedef int MHD_Result;

+#endif

+

 using namespace jsonrpc;

 using namespace std;

@@ -55,7 +59,7 @@ bool HttpServer::StartListening() {

         (MHD_is_feature_supported(MHD_FEATURE_EPOLL) == MHD_YES);

     const bool has_poll =

         (MHD_is_feature_supported(MHD_FEATURE_POLL) == MHD_YES);

-    unsigned int mhd_flags = MHD_USE_DUAL_STACK;

+    MHD_FLAG mhd_flags = MHD_USE_DUAL_STACK;

     if (has_epoll)

 // In MHD version 0.9.44 the flag is renamed to

@@ -121,8 +125,8 @@ bool HttpServer::SendResponse(const stri

   MHD_add_response_header(result, "Content-Type", "application/json");

   MHD_add_response_header(result, "Access-Control-Allow-Origin", "*");

-  int ret = MHD_queue_response(client_connection->connection,

-                               client_connection->code, result);

+  MHD_Result ret = MHD_queue_response(client_connection->connection,

+                                      client_connection->code, result);

   MHD_destroy_response(result);

   return ret == MHD_YES;

 }

@@ -139,8 +143,8 @@ bool HttpServer::SendOptionsResponse(voi

                           "origin, content-type, accept");

   MHD_add_response_header(result, "DAV", "1");

-  int ret = MHD_queue_response(client_connection->connection,

-                               client_connection->code, result);

+  MHD_Result ret = MHD_queue_response(client_connection->connection,

+                                      client_connection->code, result);

   MHD_destroy_response(result);

   return ret == MHD_YES;

 }

@@ -151,10 +155,10 @@ void HttpServer::SetUrlHandler(const str

   this->SetHandler(NULL);

 }

-int HttpServer::callback(void *cls, MHD_Connection *connection, const char *url,

-                         const char *method, const char *version,

-                         const char *upload_data, size_t *upload_data_size,

-                         void **con_cls) {

+MHD_Result HttpServer::callback(void *cls, MHD_Connection *connection, const char *url,

+                                const char *method, const char *version,

+                                const char *upload_data, size_t *upload_data_size,

+                                void **con_cls) {

   (void)version;

   if (*con_cls == NULL) {

     struct mhd_coninfo *client_connection = new mhd_coninfo;

diff --git a/src/jsonrpccpp/server/connectors/httpserver.h b/src/jsonrpccpp/server/connectors/httpserver.h

index 7785edb..74cce4f 100644

--- a/src/jsonrpccpp/server/connectors/httpserver.h

+++ b/src/jsonrpccpp/server/connectors/httpserver.h

@@ -79,7 +79,7 @@ private:

   std::map<std::string, IClientConnectionHandler *> urlhandler;

   struct sockaddr_in loopback_addr;

-  static int callback(void *cls, struct MHD_Connection *connection,

+  static MHD_Result callback(void *cls, struct MHD_Connection *connection,

                       const char *url, const char *method, const char *version,

                       const char *upload_data, size_t *upload_data_size,

                       void **con_cls);

diff --git a/src/test/testhttpserver.h b/src/test/testhttpserver.h

index f438c64..ef7429b 100644

--- a/src/test/testhttpserver.h

+++ b/src/test/testhttpserver.h

@@ -36,7 +36,7 @@ namespace jsonrpc {

             std::map<std::string,std::string> headers;

             std::string response;

-            static int callback(void *cls, struct MHD_Connection *connection, const char *url, const char *method, const char *version, const char *upload_data, size_t *upload_data_size, void **con_cls);

+            static MHD_Result callback(void *cls, struct MHD_Connection *connection, const char *url, const char *method, const char *version, const char *upload_data, size_t *upload_data_size, void **con_cls);

             static int header_iterator (void *cls, enum MHD_ValueKind kind, const char *key, const char *value);

     };