diff --git a/chrome/content/zotero/xpcom/itemTreeView.js b/chrome/content/zotero/xpcom/itemTreeView.js
index e9f54e558..5b25c77c2 100644
--- a/chrome/content/zotero/xpcom/itemTreeView.js
+++ b/chrome/content/zotero/xpcom/itemTreeView.js
@@ -1898,7 +1898,7 @@ Zotero.ItemTreeView.prototype.selectItems = function(ids) {
 	
 	var rows = [];
 	for each(var id in ids) {
-		rows.push(this._itemRowMap[id]);
+		if(this._itemRowMap[id] !== undefined) rows.push(this._itemRowMap[id]);
 	}
 	rows.sort(function (a, b) {
 		return a - b;