wp_head logs me out somewhat randomly

I’m creating a website that has a front-end login and dashboard. I have created my login form and several “authentication required” pages. They worked flawlessly.

However, one of my authentication-required pages would constantly log me out. I could go to the page, but once I went to it, if I tried to access another page that required authentication, it would log me out and I’d be forced to log in again.

I have no idea what was causing it; I used the same code that I was using for the other pages. Eventually I deleted the custom template and header files as well as the page in the WP dashboard. I figured I’d start from scratch on that page since I was obviously missing something that my eyes weren’t catching.

As soon as I did that a different page was exhibiting the same behaviour. I started commenting out code to see what could possibly be causing this and I’ve narrowed it down to the wp_head() function that’s called in the header. If I comment it out, I can stay logged in and go about my merry way. If I leave it in, I get logged out every time I visit THAT page.

I know I can’t remove it because it’s one of the most important hooks, but since I have narrowed it down to that function, I did a print_r() on the $wp_actions variable to see if there was any difference and there isn’t. This is the output:

Array
(
    [muplugins_loaded] => 1
    [registered_taxonomy] => 10
    [registered_post_type] => 11
    [plugins_loaded] => 1
    [sanitize_comment_cookies] => 1
    [setup_theme] => 1
    [load_textdomain] => 2
    [after_setup_theme] => 1
    [auth_cookie_malformed] => 1
    [auth_cookie_valid] => 1
    [set_current_user] => 1
    [init] => 1
    [widgets_init] => 1
    [register_sidebar] => 5
    [wp_register_sidebar_widget] => 14
    [wp_loaded] => 1
    [parse_request] => 1
    [send_headers] => 1
    [parse_query] => 1
    [pre_get_posts] => 1
    [posts_selection] => 1
    [wp] => 1
    [template_redirect] => 1
    [get_header] => 1
    [wp_default_scripts] => 1
)

I have added back the original page and used the same code as before, and it is working as expected. Truly perplexing.

Some more information:

– I’m using the wp_signon() function to do the logging in.
– I’m using the is_user_logged_in() function to check if the user is logged in long before the wp_head() function is called.
– If I view a page that does not require authentications, such as the home page, it works as expected: that is, I’m still logged in. But, as soon as I visit THAT page I get logged out.

Is this a bug, or am I misunderstanding something about WordPress?

Any help would be greatly appreciated. If you need code for anything, just ask.

Thank you for your time.