diff --git a/src/d_clisrv.c b/src/d_clisrv.c
index d021a09d5..f5765a437 100644
--- a/src/d_clisrv.c
+++ b/src/d_clisrv.c
@@ -10,6 +10,7 @@
 /// \file  d_clisrv.c
 /// \brief SRB2 Network game communication and protocol, all OS independent parts.
 
+#include "d_clisrv.h"
 #include <time.h>
 #ifdef __GNUC__
 #include <unistd.h> //for unlink
@@ -3620,6 +3621,8 @@ static void Got_KickCmd(UINT8 **p, INT32 playernum)
 			M_StartMessage(va(M_GetText("You have been kicked\n(%s)\n\nPress ESC\n"), reason), NULL, MM_NOTHING);
 		else if (msg == KICK_MSG_CUSTOM_BAN)
 			M_StartMessage(va(M_GetText("You have been banned\n(%s)\n\nPress ESC\n"), reason), NULL, MM_NOTHING);
+		else if (msg == KICK_MSG_SIGFAIL)
+			M_StartMessage(M_GetText("Server closed connection\n(Invalid signature)\nPress ESC\n"), NULL, MM_NOTHING);
 		else
 			M_StartMessage(M_GetText("You have been kicked by the server\n\nPress ESC\n"), NULL, MM_NOTHING);
 	}