diff --git a/chrome/content/zotero/xpcom/connector/cachedTypes.js b/chrome/content/zotero/xpcom/connector/cachedTypes.js
index c432f3823d..2156ebaf98 100644
--- a/chrome/content/zotero/xpcom/connector/cachedTypes.js
+++ b/chrome/content/zotero/xpcom/connector/cachedTypes.js
@@ -100,9 +100,14 @@ Zotero.Connector_Types = new function() {
 				var itemType = itemTypes[idOrName];
 				if(!itemType) return false;
 				
-				var itemCreatorTypes = itemType[3]/* creatorTypes */,
-					n = itemCreatorTypes.length,
-					outputTypes = new Array(n);
+				var itemCreatorTypes = itemType[3]; // creatorTypes
+				if (!itemCreatorTypes
+						// TEMP: 'note' and 'attachment' have an array containing false
+						|| (itemCreatorTypes.length == 1 && !itemCreatorTypes[0])) {
+					return [];
+				}
+				var n = itemCreatorTypes.length;
+				var outputTypes = new Array(n);
 				
 				for(var i=0; i<n; i++) {
 					var creatorType = creatorTypes[itemCreatorTypes[i]];