diff --git a/main/src/com/google/refine/commands/workspace/GetAllProjectMetadataCommand.java b/main/src/com/google/refine/commands/workspace/GetAllProjectMetadataCommand.java
index 6d75510da..018cbb7cb 100644
--- a/main/src/com/google/refine/commands/workspace/GetAllProjectMetadataCommand.java
+++ b/main/src/com/google/refine/commands/workspace/GetAllProjectMetadataCommand.java
@@ -76,10 +76,12 @@ public class GetAllProjectMetadataCommand extends Command {
                 }
                 writer.endObject();
             
-            writer.key("customMetaDataColumns");
-            JSONArray customMetaDataColumns = new JSONArray(
-                    (String)ProjectManager.singleton.getPreferenceStore().get("userMetaData"));
+            String userMeta = (String)ProjectManager.singleton.getPreferenceStore().get("userMetaData");
+            if (userMeta != null) {
+                writer.key("customMetaDataColumns");
+                JSONArray customMetaDataColumns = new JSONArray(userMeta);
                 writer.value(customMetaDataColumns);
+            }
                 
             writer.endObject();
         } catch (JSONException e) {
diff --git a/main/src/com/google/refine/io/FileProjectManager.java b/main/src/com/google/refine/io/FileProjectManager.java
index 0afd7997b..beccf4c5a 100644
--- a/main/src/com/google/refine/io/FileProjectManager.java
+++ b/main/src/com/google/refine/io/FileProjectManager.java
@@ -413,7 +413,10 @@ public class FileProjectManager extends ProjectManager {
         JSONArray jsonObjArray = metadata.getUserMetadata();
         
         try {
-            userMetadataPreference = new JSONArray((String)_preferenceStore.get(PreferenceStore.USER_METADATA_KEY));
+            String userMeta = (String)_preferenceStore.get(PreferenceStore.USER_METADATA_KEY);
+            if (userMeta == null)
+                return;
+            userMetadataPreference = new JSONArray(userMeta);
         } catch (JSONException e1) {
             logger.error(ExceptionUtils.getFullStackTrace(e1));
         }