403 cronjob htaccess

I’m lucky to have used a great cms humhub that uses the yii framework. I like him a lot and he is great.
The installation is going very well everything is working properly.
But I can not run the cronjob. I have a 403 error.
https: // mywebsite / protected / yii
I have change file permission to: 644, 711, 755. 777 nothing work
It is also protected by an htaccess file.
I’m a little panic because I love the cms humhub. It is just perfect.
Thanks for your help