403 Forbidden on access plesk panel 8.6 [help]

[Tolgay]

hi everybody,
i'm too depressed from this error : when i try to access my plesk admin panel it gives 403 forbidden error. it has became after upgrading php httpd and mysql .. i have a website on this server and everyhour it takes visitors so i can't format my plesk.. i must resolve this problem.. How can i solve this ? if anybody know please help me my plesk version is 8.6..