diff --git a/chrome/content/zotero/xpcom/storage.js b/chrome/content/zotero/xpcom/storage.js
index b030ba9fb..b0e9d55c3 100644
--- a/chrome/content/zotero/xpcom/storage.js
+++ b/chrome/content/zotero/xpcom/storage.js
@@ -1658,7 +1658,6 @@ Zotero.Sync.Storage = new function () {
 			if (fileList.length == 0) {
 				Zotero.debug('No files to add -- removing zip file');
 				tmpFile.remove(null);
-				request.stop();
 				return false;
 			}
 			
@@ -1670,9 +1669,10 @@ Zotero.Sync.Storage = new function () {
 			zw.processQueue(observer, null);
 			return true;
 		}
+		// DEBUG: Do we want to catch this?
 		catch (e) {
 			Zotero.debug(e, 1);
-			request.error(e);
+			Components.utils.reportError(e);
 			return false;
 		}
 	}
@@ -1851,9 +1851,10 @@ Zotero.Sync.Storage.ZipWriterObserver.prototype = {
 			var entry = this._zipWriter.getEntry(fileName);
 			if (!entry) {
 				var msg = "ZIP entry '" + fileName + "' not found for request '" + this._data.request.name + "'";
+				Components.utils.reportError(msg);
 				Zotero.debug(msg, 1);
 				this._zipWriter.close();
-				this._data.request.error(msg);
+				this._callback(false);
 				return;
 			}
 			originalSize += entry.realSize;
diff --git a/chrome/content/zotero/xpcom/storage/webdav.js b/chrome/content/zotero/xpcom/storage/webdav.js
index 108a4eccc..5f794d2f5 100644
--- a/chrome/content/zotero/xpcom/storage/webdav.js
+++ b/chrome/content/zotero/xpcom/storage/webdav.js
@@ -960,6 +960,10 @@ Zotero.Sync.Storage.WebDAV = (function () {
 		var created = Zotero.Sync.Storage.createUploadFile(
 			request,
 			function (data) {
+				if (!data) {
+					deferred.resolve(false);
+					return;
+				}
 				deferred.resolve(
 					Q.fcall(function () {
 						return processUploadFile(data);
diff --git a/chrome/content/zotero/xpcom/storage/zfs.js b/chrome/content/zotero/xpcom/storage/zfs.js
index a93c4c784..5462a0012 100644
--- a/chrome/content/zotero/xpcom/storage/zfs.js
+++ b/chrome/content/zotero/xpcom/storage/zfs.js
@@ -873,12 +873,19 @@ Zotero.Sync.Storage.ZFS = (function () {
 		var item = Zotero.Sync.Storage.getItemFromRequestName(request.name);
 		if (Zotero.Attachments.getNumFiles(item) > 1) {
 			var deferred = Q.defer();
-			Zotero.Sync.Storage.createUploadFile(
+			var created = Zotero.Sync.Storage.createUploadFile(
 				request,
 				function (data) {
+					if (!data) {
+						deferred.resolve(false);
+						return;
+					}
 					deferred.resolve(processUploadFile(data));
 				}
 			);
+			if (!created) {
+				return Q(false);
+			}
 			return deferred.promise;
 		}
 		else {