diff --git a/libretroshare/src/rsserver/rsinit.cc b/libretroshare/src/rsserver/rsinit.cc
index c406965d8..1e0e47278 100644
--- a/libretroshare/src/rsserver/rsinit.cc
+++ b/libretroshare/src/rsserver/rsinit.cc
@@ -116,15 +116,15 @@ RsAccounts* rsAccounts = nullptr;
 
 RsConfigOptions::RsConfigOptions()
         :
-#ifdef RS_JSONAPI
-          jsonApiPort(JsonApiServer::DEFAULT_PORT),
-          jsonApiBindAddress("127.0.0.1"),
-#endif
           autoLogin(false),
-          forcedPort(0),
           udpListenerOnly(false),
+          forcedPort(0),
           outStderr(false),
-          debugLevel(5)
+          debugLevel(5),
+#ifdef RS_JSONAPI
+          jsonApiPort(0),					// JSonAPI server is enabled in each main()
+          jsonApiBindAddress("127.0.0.1")
+#endif
 {
 }
 
diff --git a/retroshare-gui/src/main.cpp b/retroshare-gui/src/main.cpp
index 87b57f79f..8da9ab0fc 100644
--- a/retroshare-gui/src/main.cpp
+++ b/retroshare-gui/src/main.cpp
@@ -233,6 +233,8 @@ feenableexcept(FE_INVALID | FE_DIVBYZERO);
 
     RsConfigOptions conf;
 
+    conf.jsonApiPort = 0 ; // disable JSon API at start. The JSonAPI preference UI will enable it according to saved parameters.
+
 	argstream as(argc,argv);
 	as      >> option('s',"stderr"           ,conf.outStderr      ,"output to stderr instead of log file."    )
 	        >> option('u',"udp"              ,conf.udpListenerOnly,"Only listen to UDP."                      )
diff --git a/retroshare-service/src/retroshare-service.cc b/retroshare-service/src/retroshare-service.cc
index b98ff5cbb..da472944a 100644
--- a/retroshare-service/src/retroshare-service.cc
+++ b/retroshare-service/src/retroshare-service.cc
@@ -120,6 +120,8 @@ int main(int argc, char* argv[])
 	std::string prefUserString;
 	RsConfigOptions conf;
 
+	conf.jsonApiPort = JsonApiServer::DEFAULT_PORT;	// enable JSonAPI by default
+
 	argstream as(argc,argv);
 	as >> option( 's', "stderr", conf.outStderr,
 	              "output to stderr instead of log file." )