As a reference (for the future):
Specifically, from the above, you may need to check your
Order, Deny directives and correct or add them (if they do not already exist).
Beyond that, you should also check to make sure that the user & group that Apache is run as has the permissions to read, write and execute from your defined directories, and that all files and directories have proper CHMOD values (typically 0644 for PHP files and 0755 for directories - ideally, nothing should have a 0777, or world-writable CHMOD).
If this issue is a result of updating (WordPress?) permalinks, you can safely delete the
.htaccess file in the web root (make a backup first by downloading to your PC/Mac). When you click on save or update in
/wp-admin under the permalinks menu, a fresh
.htaccess file will be generated for you.
You should also scan other directories for any stray
.htaccess files to ensure that one is not clashing with another.
If generating a new one does not fix the issue, this would be the time to begin disabling all plugins. Why? Plugins have the ability to write to your
.htacccess file by default. If there’s a plugin that is making changes and making a mess of the file, only by disabling all plugins and proceeding to enable them one-by-one again will you be able to find the issue (if related to a plugin and if the error logs are not providing you with more details).
Feel free to also post your
.htaccess file here and I’ll be more than happy to take a look at it for you.