diff --git a/src/prompt.c b/src/prompt.c
index 0164440..f726750 100644
--- a/src/prompt.c
+++ b/src/prompt.c
@@ -261,7 +261,7 @@ static void prompt_onGroupInvite(ToxWindow *self, Tox *m, int friendnumber, uint
     int n = add_group_req(group_pub_key, friendnumber);
 
     if (n == -1) {
-        wprintw(self->window, "\nGroup chat queue is full. Discarding invite.\n");
+        wprintw(self->window, "\nSomething bad happened.\n");
         return;
     }
 
diff --git a/src/windows.c b/src/windows.c
index 3990186..a61d2d6 100644
--- a/src/windows.c
+++ b/src/windows.c
@@ -81,11 +81,24 @@ void on_action(Tox *m, int friendnumber, uint8_t *string, uint16_t length, void
 
 void on_nickchange(Tox *m, int friendnumber, uint8_t *string, uint16_t length, void *userdata)
 {
+    if (friendnumber < 0 || friendnumber > MAX_FRIENDS_NUM)
+        return;
+
     if (length >= TOXIC_MAX_NAME_LENGTH) {    /* length includes null byte */
         string[TOXIC_MAX_NAME_LENGTH] = L'\0';
         length = TOXIC_MAX_NAME_LENGTH+1;
     }
 
+    /* Append friendnumber to duplicate nicks to guarantee uniqueness */
+    int n = get_friendnum(string);
+
+    if (n != friendnumber && n != -1) {
+        char n_buf[strlen(string)+4];    /* must have room for chars relative to MAX_FRIENDS_NUM */
+        snprintf(n_buf, sizeof(n_buf), "%s%d", string, friendnumber);
+        strcpy(string, n_buf);
+        length = strlen(string) + 1;
+    }
+
     int i;
 
     for (i = 0; i < MAX_WINDOWS_NUM; ++i) {