diff --git a/src/backups.js b/src/backups.js
index c0cb337ce..1e4a3cc27 100644
--- a/src/backups.js
+++ b/src/backups.js
@@ -52,7 +52,6 @@ var addons = require('./addons.js'),
     safe = require('safetydance'),
     shell = require('./shell.js'),
     settings = require('./settings.js'),
-    SettingsError = require('./settings.js').SettingsError,
     tar = require('tar-fs'),
     util = require('util'),
     zlib = require('zlib');
@@ -113,7 +112,9 @@ function testConfig(backupConfig, callback) {
     assert.strictEqual(typeof callback, 'function');
 
     var func = api(backupConfig.provider);
-    if (!func) return callback(new SettingsError(SettingsError.BAD_FIELD, 'unkown storage provider'));
+    if (!func) return callback(new BackupsError(BackupsError.BAD_FIELD, 'unknown storage provider'));
+
+    if (backupConfig.format !== 'tgz' && backupConfig.format !== 'flat-file') return callback(new BackupsError(BackupsError.BAD_FIELD, 'unknown format'));
 
     api(backupConfig.provider).testConfig(backupConfig, callback);
 }
diff --git a/src/routes/settings.js b/src/routes/settings.js
index 99f7622b7..fb98103de 100644
--- a/src/routes/settings.js
+++ b/src/routes/settings.js
@@ -274,6 +274,7 @@ function setBackupConfig(req, res, next) {
     if (typeof req.body.provider !== 'string') return next(new HttpError(400, 'provider is required'));
     if (typeof req.body.retentionSecs !== 'number') return next(new HttpError(400, 'retentionSecs is required'));
     if ('key' in req.body && typeof req.body.key !== 'string') return next(new HttpError(400, 'key must be a string'));
+    if (typeof req.body.format !== 'string') return next(new HttpError(400, 'format must be a string'));
 
     settings.setBackupConfig(req.body, function (error) {
         if (error && error.reason === SettingsError.BAD_FIELD) return next(new HttpError(400, error.message));
diff --git a/webadmin/src/views/settings.js b/webadmin/src/views/settings.js
index d5312b014..630fc1f66 100644
--- a/webadmin/src/views/settings.js
+++ b/webadmin/src/views/settings.js
@@ -350,7 +350,8 @@ angular.module('Application').controller('SettingsController', ['$scope', '$loca
             var backupConfig = {
                 provider: $scope.configureBackup.provider,
                 key: $scope.configureBackup.key,
-                retentionSecs: $scope.configureBackup.retentionSecs
+                retentionSecs: $scope.configureBackup.retentionSecs,
+                format: 'tgz'
             };
 
             // only set provider specific fields, this will clear them in the db