diff --git a/chrome/content/zotero/xpcom/data/tags.js b/chrome/content/zotero/xpcom/data/tags.js
index 2f20955afd..cc77e8e5a9 100644
--- a/chrome/content/zotero/xpcom/data/tags.js
+++ b/chrome/content/zotero/xpcom/data/tags.js
@@ -580,6 +580,9 @@ Zotero.Tags = new function() {
 		}
 		
 		var tagColors = Zotero.SyncedSettings.get(libraryID, 'tagColors');
+		if (!tagColors) {
+			tagColors = [];
+		}
 		_libraryColors[libraryID] = tagColors;
 		_libraryColorsByName[libraryID] = new Map;