Error 403, In Manage Action

when i click on manage action, it redirects me to login, and then it shows

Error 403

You are not authorized to perform this action.

every time. What can be wrong ? I pass the login, authentication succeeds.

You need to login as admin

username: admin // default username for admin

password: admin // default password for admin

FYI, if you add new actions like actionManage or other actions not in the controller template. You also need to add the action to accessRules array.