diff --git a/Resources/UK/Ursula/Messages b/Resources/UK/Ursula/Messages
index ff8eb7858f40d3aacc706cf97d57d4e7ba93e8cb..6ce9ff0340d3409da33ace67eef09840f74dc357 100644
--- a/Resources/UK/Ursula/Messages
+++ b/Resources/UK/Ursula/Messages
@@ -32,6 +32,7 @@ WhatSave:Internal error - Save dialogue origin not understood in save_fill_in().
 BadType:Internal error - Bad typeface definition in %0().
 BadTRef:Internal error - Reference to undefined typeface in %0().
 
+NoContxt:Serious internal error - Block is already free or was not HtmlAlloc'd in html_close(); must exit immediately.
 HSHOvrrn:Serious internal error - HtmlStripHeaders has failed; must exit immediately.
 STCUnkwn:Serious internal error - Unknown chunk ID in memory_set_chunk_size(); must exit immediately.