diff --git a/gtc-x11vnc.sh b/gtc-x11vnc.sh
index 9d7dd1f..f6597ca 100755
--- a/gtc-x11vnc.sh
+++ b/gtc-x11vnc.sh
@@ -13,6 +13,9 @@ function usage {
 [ -z $userathost ] && usage
 [ -z $port ] && usage
 
+# kill existing Session
+tmux kill-session -t x11vnc2ssh >/dev/null 2>&1
+
 sshopts="-p $port -o BatchMode=yes -o ConnectTimeout=10 -o StrictHostKeyChecking=accept-new -o LogLevel=ERROR -o PreferredAuthentications=publickey $userathost"
 
 g_echo "Testing SSH-Connection"