diff --git a/src/clj/daisyproducer2/words.clj b/src/clj/daisyproducer2/words.clj
index 36f884d..37026e0 100644
--- a/src/clj/daisyproducer2/words.clj
+++ b/src/clj/daisyproducer2/words.clj
@@ -69,11 +69,17 @@
         untranslated (if (is-homograph? word)
                        (str/replace homograph-disambiguation "|" braille-dummy-text)
                        untranslated)]
-    (cond-> word
-      (and (contains? word :uncontracted) (nil? (:uncontracted word)))
-      (assoc :uncontracted (louis/translate untranslated (louis/translator (louis/get-tables 1 params))))
-      (and (contains? word :contracted) (nil? (:contracted word)))
-      (assoc :contracted (louis/translate untranslated (louis/translator (louis/get-tables 2 params)))))))
+    (try
+      (cond-> word
+        (and (contains? word :uncontracted) (nil? (:uncontracted word)))
+        (assoc :uncontracted (louis/translate untranslated (louis/translator (louis/get-tables 1 params))))
+        (and (contains? word :contracted) (nil? (:contracted word)))
+        (assoc :contracted (louis/translate untranslated (louis/translator (louis/get-tables 2 params)))))
+      ;; if there was a problem with translating the word, simply return the
+      ;; word without the braille added. That will serve as an indication that
+      ;; the braille translation failed
+      (catch clojure.lang.ExceptionInfo e
+        word))))
 
 (defn grades [grade]
   (case (int grade) ; convert grade into a list of grades
diff --git a/src/cljs/daisyproducer2/words/input_fields.cljs b/src/cljs/daisyproducer2/words/input_fields.cljs
index 924b4d3..061f27c 100644
--- a/src/cljs/daisyproducer2/words/input_fields.cljs
+++ b/src/cljs/daisyproducer2/words/input_fields.cljs
@@ -59,3 +59,7 @@
 (defn disabled-field [value]
   [:div.field
    [:input.input {:type "text" :value value :disabled "disabled"}]])
+
+(defn invalid-field []
+  [:div.field
+   [:input.input.is-danger {:type "text" :disabled "disabled"}]])
diff --git a/src/cljs/daisyproducer2/words/unknown.cljs b/src/cljs/daisyproducer2/words/unknown.cljs
index d63800c..fab84ca 100644
--- a/src/cljs/daisyproducer2/words/unknown.cljs
+++ b/src/cljs/daisyproducer2/words/unknown.cljs
@@ -217,23 +217,26 @@
   (let [grade @(rf/subscribe [::grade/grade])
         {:keys [uuid untranslated uncontracted contracted type homograph-disambiguation
                 hyphenated invalid-hyphenated]} @(rf/subscribe [::word id])]
-    [:tr
-     [:td untranslated]
-     (when (#{0 1} grade)
-       (if uncontracted
-         [:td [fields/input-field :unknown uuid :uncontracted validation/braille-valid?]]
-         [:td]))
-     (when (#{0 2} grade)
-       (if contracted
-         [:td [fields/input-field :unknown uuid :contracted validation/braille-valid?]]
-         [:td]))
-     [:td (if hyphenated
-            [fields/input-field :unknown uuid :hyphenated #(validation/hyphenation-valid? % untranslated)]
-            [fields/disabled-field invalid-hyphenated])]
-     [:td {:width "8%"} (get words/type-mapping type (tr [:unknown]))]
-     [:td {:width "8%"} homograph-disambiguation]
-     [:td [fields/local-field :unknown uuid]]
-     [:td {:width "8%"} [buttons uuid]]]))
+    ;; if we have neither the uncontracted nor the contracted field,
+    ;; most likely the braille translation failed
+    (let [valid (or uncontracted contracted)]
+      [:tr
+       [:td untranslated]
+       (when (#{0 1} grade)
+         (if uncontracted
+           [:td [fields/input-field :unknown uuid :uncontracted validation/braille-valid?]]
+           [:td [fields/invalid-field]]))
+       (when (#{0 2} grade)
+         (if contracted
+           [:td [fields/input-field :unknown uuid :contracted validation/braille-valid?]]
+           [:td [fields/invalid-field]]))
+       [:td (if hyphenated
+              [fields/input-field :unknown uuid :hyphenated #(validation/hyphenation-valid? % untranslated)]
+              [fields/disabled-field invalid-hyphenated])]
+       [:td {:width "8%"} (get words/type-mapping type (tr [:unknown]))]
+       [:td {:width "8%"} homograph-disambiguation]
+       [:td (when valid [fields/local-field :unknown uuid])]
+       [:td {:width "8%"} (when valid [buttons uuid])]])))
 
 (defn unknown-words []
   (let [words @(rf/subscribe [::words-sorted])