Q: I am using the drupal webform module to implement a 'Contact us' type form but when an anonymous user tries to submit the form they get this error: 'You are not authorized to access this page.' How can I fix this?
A: Make sure that the webform node is marked as 'published'.

The drupal webform module provides a very good alternative to the sometimes limiting drupal 'Contact Us' functionality. It provides more flexibility allowing you implement a 'Contact Us' form that more closly matches your target web design. For example it allows you to more easily include a google map and other rich information.

There is however a common gotcha with webforms - for anonymous users to be able to successfully submit a form, the corresponding webform node must be marked as published.

Normally when you create a node, say a page node or a blog post or something, its 'published' flag (in its setting page) defaults to set/true, so that when you save the node it is immediately published. For some reason on the webform's settings page this flag defaults to unset/false, so before you save the node you must make sure to manually mark it as published and anonymous users should no longer get the error message when they submit your form.