Index: misc_gui.c
===================================================================
--- misc_gui.c	(revision 6500)
+++ misc_gui.c	(working copy)
@@ -1318,6 +1318,8 @@
 static void SaveLoadDlgWndProc(Window *w, WindowEvent *e)
 {
 	static FiosItem o_dir;
+	WindowClass wc;
+	WindowNumber wn;
 
 	switch (e->event) {
 	case WE_CREATE: { /* Set up OPENTTD button */
@@ -1461,13 +1463,18 @@
 	case WE_TIMEOUT:
 		if (HASBIT(w->click_state, 11)) { /* Delete button clicked */
 			if (!FiosDelete(OTTD2FS(WP(w,querystr_d).text.buf))) {
+				/* MR 2006-09-26; Restore the w pointer after calling ShowErrorMessage, because window list can change */
+				wc = w->window_class;
+				wn = w->window_number;
+
 				ShowErrorMessage(INVALID_STRING_ID, STR_4008_UNABLE_TO_DELETE_FILE, 0, 0);
+
+				w = FindWindowById(wc, wn);
 			} else {
 				BuildFileList();
 				/* Reset file name to current date on successfull delete */
 				if (_saveload_mode == SLD_SAVE_GAME) GenerateFileName();
 			}
-
 			UpdateTextBufferSize(&WP(w, querystr_d).text);
 			SetWindowDirty(w);
 		} else if (HASBIT(w->click_state, 12)) { /* Save button clicked */