Index: base/setup/usetup/interface/usetup.c
===================================================================
--- base/setup/usetup/interface/usetup.c	(revision 62436)
+++ base/setup/usetup/interface/usetup.c	(working copy)
@@ -2453,8 +2454,27 @@
                                          FileSystemList->Selected);
                 if (!NT_SUCCESS(Status))
                 {
+                    CHAR Buffer[MAX_PATH];
                     DPRINT1("FormatPartition() failed with status 0x%08lx\n", Status);
-                    /* FIXME: show an error dialog */
+                    // Show an error dialog
+                    sprintf(Buffer,
+                            "Setup is currently unable to format the partition:\n %S.\n"
+                            "\n"
+                            "  \x07  Press Enter to quit Setup.",
+                            PathBuffer);
+                    
+                    PopupError(Buffer,
+                               MUIGetString(STRING_REBOOTCOMPUTER),
+                               NULL, POPUP_WAIT_NONE);
+                    while (TRUE)
+                    {
+                        CONSOLE_ConInKey(Ir);
+                        if (Ir->Event.KeyEvent.wVirtualKeyCode == VK_RETURN) /* ENTER */
+                        {
+                            return QUIT_PAGE;
+                        }
+                    }
+                    
                     return QUIT_PAGE;
                 }