I have a Windows 2008 Server, with MySQL and Plesk 12.0.18. It worked without problems till yesterday. Now, when trying to access the login page I get the following error:

500 - Internal server error.
There is a problem with the resource you are looking for, and it cannot be displayed.

I have tried connecting via Remote Desktop to the server and launch it from the server itself, but I get the following error:

HTTP Error 500.0 - Internal Server Error
An unknown FastCGI error occured Detailed Error Information
Module FastCgiModule
Notification ExecuteRequestHandler
Handler PleskEngine-FastCGI-php
Error Code 0x800700d8
Requested URL https://localhost:8443/index.php
Physical Path C:\Parallels\Plesk\admin\htdocs\index.php
Logon Method Anonymous
Logon User Anonymous

I have made no modifications in Plesk since it was installed.

Some idea of what the problem could be?

These are the last entries in the php_error log:

[2015-09-23 14:03:45] Zend_Controller_Exception: Permission denied.#0 C:\Parallels\Plesk\admin\plib\CommonPanel\Controller\Action\Abstract.php(191): CommonPanel_Controller_Action_Abstract->_checkForgeryProtectionToken()

1 C:\Parallels\Plesk\admin\externals\Zend\Controller\Action.php(502): CommonPanel_Controller_Action_Abstract->preDispatch()

2 C:\Parallels\Plesk\admin\externals\Zend\Controller\Dispatcher\Standard.php(295): Zend_Controller_Action->dispatch('errorAction')

3 C:\Parallels\Plesk\admin\externals\Zend\Controller\Front.php(954): Zend_Controller_Dispatcher_Standard->dispatch(Object(Zend_Controller_Request_Http), Object(Zend_Controller_Response_Http))

4 C:\Parallels\Plesk\admin\plib\Application\Web.php(38): Zend_Controller_Front->dispatch(NULL)

5 C:\Parallels\Plesk\admin\htdocs\application.php(15): Plesk\Application_Web->run()

6 {main}

file: C:\Parallels\Plesk\admin\externals\Zend\Controller\Plugin\Broker.php line: 336 code: 0 trace: #0 C:\Parallels\Plesk\admin\externals\Zend\Controller\Front.php(965): Zend_Controller_Plugin_Broker->postDispatch(Object(Zend_Controller_Request_Http))

1 C:\Parallels\Plesk\admin\plib\Application\Web.php(38): Zend_Controller_Front->dispatch(NULL)

2 C:\Parallels\Plesk\admin\htdocs\application.php(15): Plesk\Application_Web->run()

#3 {main}

0 C:\Parallels\Plesk\admin\plib\CommonPanel\Controller\Action\Abstract.php(191): CommonPanel_Controller_Action_Abstract->_checkForgeryProtectionToken()

1 C:\Parallels\Plesk\admin\externals\Zend\Controller\Action.php(502): CommonPanel_Controller_Action_Abstract->preDispatch()

2 C:\Parallels\Plesk\admin\externals\Zend\Controller\Dispatcher\Standard.php(295): Zend_Controller_Action->dispatch('errorAction')

3 C:\Parallels\Plesk\admin\externals\Zend\Controller\Front.php(954): Zend_Controller_Dispatcher_Standard->dispatch(Object(Zend_Controller_Request_Http), Object(Zend_Controller_Response_Http))

4 C:\Parallels\Plesk\admin\plib\Application\Web.php(38): Zend_Controller_Front->dispatch(NULL)

5 C:\Parallels\Plesk\admin\htdocs\application.php(15): Plesk\Application_Web->run()

6 {main}

[2015-09-25 03:20:46] ERR [panel] Task not responding: id=467, pid=131496, type=panel-update.

The first entry 2015-09-23 was pevious to the error in Plesk.