diff --git a/toolkit/components/url-classifier/Classifier.cpp b/toolkit/components/url-classifier/Classifier.cpp
index 50c554d3230e..001a78e0b668 100644
--- a/toolkit/components/url-classifier/Classifier.cpp
+++ b/toolkit/components/url-classifier/Classifier.cpp
@@ -149,6 +149,28 @@ Classifier::SetupPathNames()
   return NS_OK;
 }
 
+nsresult
+Classifier::CreateStoreDirectory()
+{
+  // Ensure the safebrowsing directory exists.
+  bool storeExists;
+  nsresult rv = mStoreDirectory->Exists(&storeExists);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  if (!storeExists) {
+    rv = mStoreDirectory->Create(nsIFile::DIRECTORY_TYPE, 0755);
+    NS_ENSURE_SUCCESS(rv, rv);
+  } else {
+    bool storeIsDir;
+    rv = mStoreDirectory->IsDirectory(&storeIsDir);
+    NS_ENSURE_SUCCESS(rv, rv);
+    if (!storeIsDir)
+      return NS_ERROR_FILE_DESTINATION_NOT_DIR;
+  }
+
+  return NS_OK;
+}
+
 nsresult
 Classifier::Open(nsIFile& aCacheDirectory)
 {
@@ -169,22 +191,10 @@ Classifier::Open(nsIFile& aCacheDirectory)
   rv = RecoverBackups();
   NS_ENSURE_SUCCESS(rv, rv);
 
-  // Ensure the safebrowsing directory exists.
-  bool storeExists;
-  rv = mStoreDirectory->Exists(&storeExists);
+  // Make sure the main store directory exists.
+  rv = CreateStoreDirectory();
   NS_ENSURE_SUCCESS(rv, rv);
 
-  if (!storeExists) {
-    rv = mStoreDirectory->Create(nsIFile::DIRECTORY_TYPE, 0755);
-    NS_ENSURE_SUCCESS(rv, rv);
-  } else {
-    bool storeIsDir;
-    rv = mStoreDirectory->IsDirectory(&storeIsDir);
-    NS_ENSURE_SUCCESS(rv, rv);
-    if (!storeIsDir)
-      return NS_ERROR_FILE_DESTINATION_NOT_DIR;
-  }
-
   mCryptoHash = do_CreateInstance(NS_CRYPTO_HASH_CONTRACTID, &rv);
   NS_ENSURE_SUCCESS(rv, rv);
 
@@ -219,6 +229,8 @@ Classifier::Reset()
   mBackupDirectory->Remove(true);
   mToDeleteDirectory->Remove(true);
 
+  CreateStoreDirectory();
+
   mTableFreshness.Clear();
   RegenActiveTables();
 }
diff --git a/toolkit/components/url-classifier/Classifier.h b/toolkit/components/url-classifier/Classifier.h
index ff11d91fca77..bacad2e90cc8 100644
--- a/toolkit/components/url-classifier/Classifier.h
+++ b/toolkit/components/url-classifier/Classifier.h
@@ -71,6 +71,7 @@ public:
                             PrefixArray* aNoiseEntries);
 private:
   void DropStores();
+  nsresult CreateStoreDirectory();
   nsresult SetupPathNames();
   nsresult RecoverBackups();
   nsresult CleanToDelete();
diff --git a/toolkit/components/url-classifier/tests/unit/test_streamupdater.js b/toolkit/components/url-classifier/tests/unit/test_streamupdater.js
index c934890dba0e..24254cde1f82 100644
--- a/toolkit/components/url-classifier/tests/unit/test_streamupdater.js
+++ b/toolkit/components/url-classifier/tests/unit/test_streamupdater.js
@@ -454,7 +454,7 @@ function run_test()
     testValidForwardMAC,
     testInvalidForwardMAC,
     testNoForwardMAC,
-    testRekey,
+    testRekey
   ]);
 }