diff --git a/www/common/cryptpad-common.js b/www/common/cryptpad-common.js
index a2a2fe7a9..5ee07946b 100644
--- a/www/common/cryptpad-common.js
+++ b/www/common/cryptpad-common.js
@@ -138,7 +138,7 @@ define([
         }
         postMessage("SET", {
             key:['drive'],
-            value: data
+            value: data.drive
         }, function (obj) {
             cb(obj);
         }, {
diff --git a/www/common/proxy-manager.js b/www/common/proxy-manager.js
index 1257f3ad4..7f20ae5b6 100644
--- a/www/common/proxy-manager.js
+++ b/www/common/proxy-manager.js
@@ -1036,6 +1036,9 @@ define([
     var isInSharedFolder = _isInSharedFolder;
 
     /* Generic: doesn't need access to a proxy */
+    var isValidDrive = function (Env, obj) {
+        return Env.user.userObject.isValidDrive(obj);
+    };
     var isFile = function (Env, el, allowStr) {
         return Env.user.userObject.isFile(el, allowStr);
     };
@@ -1131,6 +1134,7 @@ define([
             getUserObjectPath: callWithEnv(getUserObjectPath),
             isDuplicateOwned: callWithEnv(isDuplicateOwned),
             // Generic
+            isValidDrive: callWithEnv(isValidDrive),
             isFile: callWithEnv(isFile),
             isFolder: callWithEnv(isFolder),
             isSharedFolder: callWithEnv(isSharedFolder),
diff --git a/www/common/userObject.js b/www/common/userObject.js
index 39b55484a..fe99f9935 100644
--- a/www/common/userObject.js
+++ b/www/common/userObject.js
@@ -72,8 +72,22 @@ define([
             a[TRASH] = {};
             a[FILES_DATA] = {};
             a[TEMPLATE] = [];
+            a[SHARED_FOLDERS] = {};
             return a;
         };
+
+        var type = function (dat) {
+            return dat === null?  'null': Array.isArray(dat)?'array': typeof(dat);
+        };
+        exp.isValidDrive = function (obj) {
+            var base = exp.getStructure();
+            return typeof (obj) === "object" &&
+                    Object.keys(base).every(function (key) {
+                        console.log(key, obj[key], type(obj[key]));
+                        return obj[key] && type(base[key]) === type(obj[key]);
+                    });
+        };
+
         var getHrefArray = function () {
             return [TEMPLATE];
         };
diff --git a/www/drive/inner.js b/www/drive/inner.js
index ffcb33bba..3e593f209 100644
--- a/www/drive/inner.js
+++ b/www/drive/inner.js
@@ -4245,6 +4245,10 @@ define([
                 return;
             }
             history.sfId = false;
+
+            var ok = manager.isValidDrive(obj.drive);
+            if (!ok) { return; }
+
             copyObjectValue(files, obj.drive);
             appStatus.isReady = true;
             refresh();