I am currently using ExpressionEngine 2.5.5 and have a template with multiple conditional statements...
{if logged_in && member_group == '1' || member_group == '7'}
<div>Content</div>
{/if}
{if logged_in && member_group != '1' || member_group != '7'}
<div class="authNotice">
<p>You are not authorized to view this content.</p>
</div>
{/if}
{if logged_out}
<div class="authNotice">
<p>Please <a href="#">Log In</a> or <a href="#">Register</a>.</p>
</div>
{/if}
The second statement does not work properly as it displays the message "You are not authorized to view this content" even if the conditions are met.
Does anyone know the best practice for combining these three conditions in a single template?
Your second condition is always true. You should change
{if logged_in && member_group != '1' || member_group != '7'}
to
{if logged_in && member_group != '1' && member_group != '7'}
DISCLAIMER: I have no idea what ExpressionEngine is ;)