Auto sign-in to Organic groups homepage I have setup a site where users can register as a certain type of user. Once registered, an organic group node is created for them and they can then invite other users into their group.

Can anyone advice me how the group owner and the invited members to automatically login to the group page and how to restrict users to a single group?
The way I accomplished this was to use Rules to detect when a user logs into the site and also when content is about to be viewed.

Rules provides a programmatic  area in the "DO" feature of the Rule. I execute some php code to detect the group the user belongs to and redirect using drupal_goto.