diff --git a/leakcanary-analyzer/src/main/java/com/squareup/leakcanary/HahaHelper.java b/leakcanary-analyzer/src/main/java/com/squareup/leakcanary/HahaHelper.java
index bb09ad9211..b322c162ed 100644
--- a/leakcanary-analyzer/src/main/java/com/squareup/leakcanary/HahaHelper.java
+++ b/leakcanary-analyzer/src/main/java/com/squareup/leakcanary/HahaHelper.java
@@ -83,6 +83,7 @@ static String valueAsString(Object value) {
 
   /** Given a string instance from the heap dump, this returns its actual string value. */
   static String asString(Object stringObject) {
+    checkNotNull(stringObject, "stringObject");
     Instance instance = (Instance) stringObject;
     List<ClassInstance.FieldValue> values = classInstanceValues(instance);
 
diff --git a/leakcanary-analyzer/src/main/java/com/squareup/leakcanary/HeapAnalyzer.java b/leakcanary-analyzer/src/main/java/com/squareup/leakcanary/HeapAnalyzer.java
index d57663a534..ebd5617f6e 100644
--- a/leakcanary-analyzer/src/main/java/com/squareup/leakcanary/HeapAnalyzer.java
+++ b/leakcanary-analyzer/src/main/java/com/squareup/leakcanary/HeapAnalyzer.java
@@ -211,10 +211,19 @@ private String generateRootKey(RootObj root) {
 
   private Instance findLeakingReference(String key, Snapshot snapshot) {
     ClassObj refClass = snapshot.findClass(KeyedWeakReference.class.getName());
+    if (refClass == null) {
+      throw new IllegalStateException(
+          "Could not find the " + KeyedWeakReference.class.getName() + " class in the heap dump.");
+    }
     List<String> keysFound = new ArrayList<>();
     for (Instance instance : refClass.getInstancesList()) {
       List<ClassInstance.FieldValue> values = classInstanceValues(instance);
-      String keyCandidate = asString(fieldValue(values, "key"));
+      Object keyFieldValue = fieldValue(values, "key");
+      if (keyFieldValue == null) {
+        keysFound.add(null);
+        continue;
+      }
+      String keyCandidate = asString(keyFieldValue);
       if (keyCandidate.equals(key)) {
         return fieldValue(values, "referent");
       }
diff --git a/leakcanary-android/src/main/res/values/leak_canary_strings.xml b/leakcanary-android/src/main/res/values/leak_canary_strings.xml
index b4faa52d09..e39f1f5390 100644
--- a/leakcanary-android/src/main/res/values/leak_canary_strings.xml
+++ b/leakcanary-android/src/main/res/values/leak_canary_strings.xml
@@ -34,7 +34,7 @@
   <string name="leak_canary_storage_permission_activity_label">Storage permission</string>
   <string name="leak_canary_toast_heap_dump">Dumping memory, app will freeze. Brrrr.</string>
   <string name="leak_canary_delete">Delete</string>
-  <string name="leak_canary_failure_report">"Please report this failure to http://github.com/square/leakcanary\n"</string>
+  <string name="leak_canary_failure_report">"Please report this failure to http://github.com/square/leakcanary and share the heapdump file that caused it.\n"</string>
   <string name="leak_canary_delete_all">Delete all</string>
   <string name="leak_canary_delete_all_leaks_title">Are you sure you want to delete all leaks?</string>
   <string name="leak_canary_could_not_save_title">Could not save result.</string>