Hello, 

I am getting the same problem, 

I have followed below steps and got success:-

- Open terminal.

- Go on own Magento project directory.

Ex. I am using the lamp server in the localhost so my path is var/www/Html/magento23

where magento23 is my Magento project directory.

- Type a command "cd /var/www/Html/magento23" and press enter button.

- Currently, my current terminal directory is magento23.

- Run the command "chmod -R 777 var/* generated/* pub/static/"
- If you will use ubuntu OS so please run the command "sudo chmod -R 777 var/* generated/* pub/static/".