After Migrating to another server either can't login to admin or after login the error below comes out any solution? Thanks in advance.

[User Error] singleton() Called without a class
GET /admin

Line 258 in /data/13/1/137/157/1300483/user/1392268/htdocs/home/sapphire/core/Core.php
Source

249 * data (e.g. the custom SilverStripe static handling).
250 *
251 * @uses Object::strong_create()
252 *
253 * @param string $className
254 * @return Object
255 */
256 function singleton($className) {
257 global $_SINGLETONS;
258 if(!isset($className)) user_error("singleton() Called without a class", E_USER_ERROR);
259 if(!is_string($className)) user_error("singleton() passed bad class_name: " . var_export($className,true), E_USER_ERROR);
260 if(!isset($_SINGLETONS[$className])) {
261 if(!class_exists($className)) user_error("Bad class to singleton() - $className", E_USER_ERROR);
262 $_SINGLETONS[$className] = Object::strong_create($className,null, true);
263 if(!$_SINGLETONS[$className]) user_error("singleton() Unknown class '$className'", E_USER_ERROR);
264 }

Trace

* singleton() Called without a class
Line 258 of Core.php
* singleton()
Line 430 of LeftAndMain.php
* LeftAndMain->MainMenu()
* call_user_func_array(Array,Array)
Line 318 of ViewableData.php
* ViewableData->obj(MainMenu)
Line 1077 of LeftAndMain.php
* LeftAndMain->SectionTitle()
* call_user_func_array(Array,Array)
Line 408 of ViewableData.php
* ViewableData->XML_val(SectionTitle,,1)
Line 20 of .cache.data.13.1.137.157.1300483.user.1392268.htdocs.home.cms.templates.LeftAndMain.ss
* include(/data/13/1/137/157/1300483/user/1392268/htdocs/home/silverstripe-cache/.cache.data.13.1.137.157.1300483.user.1392268.htdocs.home.cms.templates.LeftAndMain.ss)
Line 354 of SSViewer.php
* SSViewer->process(CMSMain)
Line 175 of Controller.php
* Controller->handleAction(HTTPRequest)
Line 129 of RequestHandler.php
* RequestHandler->handleRequest(HTTPRequest)
Line 122 of Controller.php
* Controller->handleRequest(HTTPRequest)
Line 277 of Director.php
* Director::handleRequest(HTTPRequest,Session)
Line 121 of Director.php
* Director::direct(/admin)
Line 118 of main.php