403. You don’t have permission to access this resource error

I tried to delete my existing WordPress installation.

What could not be deleted were the apache2, mysql and php folders because ‘the folder or file in it is open in another program.’

I restarted to ensure no programs were running.

Because I couldn’t delete the apache2, mysql and php folders, I tried to reinstall WordPress on my computer hoping the reinstall would use the new apache2, mysql and php folders.

When I typed ‘localhost/wordpress/wp-admin’ I get a page that simply reads:
‘Forbidden. You don’t have permission to access this resource’.

This is rendering me unable to access the regular WordPress interface.