diff --git a/application/Espo/Core/Upgrades/Actions/Base.php b/application/Espo/Core/Upgrades/Actions/Base.php
index f37fda6a4a..076035fc1f 100644
--- a/application/Espo/Core/Upgrades/Actions/Base.php
+++ b/application/Espo/Core/Upgrades/Actions/Base.php
@@ -34,6 +34,8 @@ abstract class Base
 
     private $entityManager;
 
+    private $helper;
+
     protected $data;
 
     protected $params = null;
@@ -131,7 +133,7 @@ abstract class Base
         return $this->config;
     }
 
-    protected function getEntityManager()
+    public function getEntityManager()
     {
         if (!isset($this->entityManager)) {
             $this->entityManager = $this->getContainer()->get('entityManager');
@@ -195,10 +197,15 @@ abstract class Base
             $res &= $this->checkVersions($manifest['acceptableVersions'], $this->getConfig()->get('version'), 'Your EspoCRM version doesn\'t match for this installation package.');
         }
 
+        //check dependencies
+        if (!empty($manifest['dependencies'])) {
+            $res &= $this->checkDependencies($manifest['dependencies']);
+        }
+
         return (bool) $res;
     }
 
-    protected function checkVersions($versionList, $currentVersion, $errorMessage = '')
+    public function checkVersions($versionList, $currentVersion, $errorMessage = '')
     {
         if (empty($versionList)) {
             return true;
@@ -212,7 +219,7 @@ abstract class Base
             $semver = new SemVer\version($currentVersion);
         } catch (\Exception $e) {
             $GLOBALS['log']->error('Cannot recognize currentVersion ['.$currentVersion.'], error: '.$e->getMessage().'.');
-            return;
+            return false;
         }
 
         foreach ($versionList as $version) {
@@ -251,6 +258,11 @@ abstract class Base
         return true;
     }
 
+    protected function checkDependencies($dependencyList)
+    {
+        return true;
+    }
+
     /**
      * Run scripts by type
      * @param  string $type Ex. "before", "after"
@@ -550,4 +562,15 @@ abstract class Base
         $backupPath = $this->getPath('backupPath');
         return $this->copy('', array($backupPath, self::FILES), false, $fullFileList);
     }
+
+    protected function getHelper()
+    {
+        if (!isset($this->helper)) {
+            $this->helper = new Helper();
+        }
+
+        $this->helper->setActionObject($this);
+
+        return $this->helper;
+    }
 }
\ No newline at end of file
diff --git a/application/Espo/Core/Upgrades/Actions/Extension/Install.php b/application/Espo/Core/Upgrades/Actions/Extension/Install.php
index efc397fafb..9e7dcd2ad7 100644
--- a/application/Espo/Core/Upgrades/Actions/Extension/Install.php
+++ b/application/Espo/Core/Upgrades/Actions/Extension/Install.php
@@ -138,7 +138,7 @@ class Install extends \Espo\Core\Upgrades\Actions\Base\Install
 
         $data = array(
             'id' => $this->getProcessId(),
-            'name' => $manifest['name'],
+            'name' => trim($manifest['name']),
             'isInstalled' => true,
             'version' => $manifest['version'],
             'fileList' => $fileList,
@@ -171,8 +171,8 @@ class Install extends \Espo\Core\Upgrades\Actions\Base\Install
      * Throw an exception and remove package files.
      * Redeclared to prevent of deleting a package of installed extension.
      *
-     * @param  string $errorMessage [description]
-     * @return [type]               [description]
+     * @param  string $errorMessage
+     * @return void
      */
     protected function throwErrorAndRemovePackage($errorMessage = '')
     {
@@ -211,7 +211,8 @@ class Install extends \Espo\Core\Upgrades\Actions\Base\Install
         $this->executeAction(ExtensionManager::DELETE, array('id' => $extensionEntity->get('id')));
     }
 
-
-
-
+    protected function checkDependencies($dependencyList)
+    {
+        return $this->getHelper()->checkDependencies($dependencyList);
+    }
 }
diff --git a/application/Espo/Core/Upgrades/Actions/Extension/Upload.php b/application/Espo/Core/Upgrades/Actions/Extension/Upload.php
index 9eea1c4d0b..b1254b5215 100644
--- a/application/Espo/Core/Upgrades/Actions/Extension/Upload.php
+++ b/application/Espo/Core/Upgrades/Actions/Extension/Upload.php
@@ -24,5 +24,8 @@ namespace Espo\Core\Upgrades\Actions\Extension;
 
 class Upload extends \Espo\Core\Upgrades\Actions\Base\Upload
 {
-
+    protected function checkDependencies($dependencyList)
+    {
+        return $this->getHelper()->checkDependencies($dependencyList);
+    }
 }
\ No newline at end of file
diff --git a/application/Espo/Core/Upgrades/Actions/Helper.php b/application/Espo/Core/Upgrades/Actions/Helper.php
new file mode 100644
index 0000000000..0853f5b642
--- /dev/null
+++ b/application/Espo/Core/Upgrades/Actions/Helper.php
@@ -0,0 +1,77 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM - Open Source CRM application.
+ * Copyright (C) 2014-2015 Yuri Kuznetsov, Taras Machyshyn, Oleksiy Avramenko
+ * Website: http://www.espocrm.com
+ *
+ * EspoCRM is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * EspoCRM is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with EspoCRM. If not, see http://www.gnu.org/licenses/.
+ ************************************************************************/
+
+namespace Espo\Core\Upgrades\Actions;
+
+use Espo\Core\Exceptions\Error;
+
+class Helper
+{
+    private $actionObject;
+
+    public function __construct($actionObject = null)
+    {
+        if (isset($actionObject)) {
+            $this->setActionObject($actionObject);
+        }
+    }
+
+    public function setActionObject(\Espo\Core\Upgrades\Actions\Base $actionObject)
+    {
+        $this->actionObject = $actionObject;
+    }
+
+    protected function getActionObject()
+    {
+        return $this->actionObject;
+    }
+
+    /**
+     * Check dependencies
+     *
+     * @param  array | string $dependencyList
+     *
+     * @return bool
+     */
+    public function checkDependencies($dependencyList)
+    {
+        if (!is_array($dependencyList)) {
+            $dependencyList = (array) $dependencyList;
+        }
+
+        $actionObject = $this->getActionObject();
+
+        foreach ($dependencyList as $extensionName => $extensionVersion) {
+            $dependencyExtensionEntity = $actionObject->getEntityManager()->getRepository('Extension')->where(array(
+                'name' => trim($extensionName),
+                'isInstalled' => true,
+            ))->findOne();
+
+            $errorMessage = 'Dependency Error: The extension "'.$extensionName.'" with version "'.$extensionVersion.'" is missing.';
+            if (!isset($dependencyExtensionEntity) || !$actionObject->checkVersions($extensionVersion, $dependencyExtensionEntity->get('version'), $errorMessage)) {
+                throw new Error($errorMessage);
+            }
+        }
+
+        return true;
+    }
+}