Error in magento 2.3 Class Does Not Exist in backend and frontend

Question

I upload my magento 2.3 on my server, so when i navigate in the frontend the navbar is disappeared see the photo enter image description here so when change the mode to developer, to see the error in backend output print this error: Class Magento\Catalog\Model\Category\ Attribute\Backend\Sortby does not exist So What's going on?.

Answer 1

You have space in class name after Category - may by that is reason why class reader cannot find class.