403 Error When Adding Shipping Method

403 Forbidden error when I try to create a new shipping method.

Using PHP 7.1 on cpanel

cpanel error log just shows

File not found [/home2/shopqent/public_html/403.shtml]

I also get the error when I try a product import

Guessing it's a file permission error, but don't know where to look

Looks like it was mod_security. fixed by host