Title: php errors – smooth wall
Last modified: August 22, 2016

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# php errors – smooth wall

 *  Resolved [macpolski2](https://wordpress.org/support/users/macpolski2/)
 * (@macpolski2)
 * [11 years, 8 months ago](https://wordpress.org/support/topic/php-errors-smooth-wall/)
 * I am not sure but I believe that I need to open a port on my smooth wall firewall–
   to allow login to duo-security. These are the errors that are posted. If I setup
   the server outside of the firewall everything is fine. Thank you.
 * > Warning: file_get_contents([https://api-0200d496.duosecurity.com/auth/v2/ping](https://api-0200d496.duosecurity.com/auth/v2/ping))[
   > function.file-get-contents]: failed to open stream: Connection refused in /
   > Library/WebServer/Documents/BSRNew/wp-content/plugins/duo-wordpress/duo_wordpress.
   > php on line 539
   > Warning: Cannot modify header information – headers already sent by (output
   > started at /Library/WebServer/Documents/BSRNew/wp-content/plugins/duo-wordpress/
   > duo_wordpress.php:539) in /Library/WebServer/Documents/BSRNew/wp-content/plugins/
   > duo-wordpress/duo_wordpress.php on line 612
   > Warning: Cannot modify header information – headers already sent by (output
   > started at /Library/WebServer/Documents/BSRNew/wp-content/plugins/duo-wordpress/
   > duo_wordpress.php:539) in /Library/WebServer/Documents/BSRNew/wp-includes/pluggable.
   > php on line 737
   > Warning: Cannot modify header information – headers already sent by (output
   > started at /Library/WebServer/Documents/BSRNew/wp-content/plugins/duo-wordpress/
   > duo_wordpress.php:539) in /Library/WebServer/Documents/BSRNew/wp-includes/pluggable.
   > php on line 738
   > Warning: Cannot modify header information – headers already sent by (output
   > started at /Library/WebServer/Documents/BSRNew/wp-content/plugins/duo-wordpress/
   > duo_wordpress.php:539) in /Library/WebServer/Documents/BSRNew/wp-includes/pluggable.
   > php on line 739
   > Warning: Cannot modify header information – headers already sent by (output
   > started at /Library/WebServer/Documents/BSRNew/wp-content/plugins/duo-wordpress/
   > duo_wordpress.php:539) in /Library/WebServer/Documents/BSRNew/wp-includes/pluggable.
   > php on line 934
 * [https://wordpress.org/plugins/duo-wordpress/](https://wordpress.org/plugins/duo-wordpress/)

Viewing 1 replies (of 1 total)

 *  Plugin Author [Duo Security](https://wordpress.org/support/users/duosecurity/)
 * (@duosecurity)
 * [11 years, 8 months ago](https://wordpress.org/support/topic/php-errors-smooth-wall/#post-5274168)
 * Yes, this looks like a firewall issue.
 * The error indicates a problem connecting to [https://api-0200d496.duosecurity.com](https://api-0200d496.duosecurity.com),
   ie. (currently) 54.241.191.167 on port TCP 443
 * Note that your API Hostname can change to a different IP address at any time.
   We advise allowing outbound connectivity to all IPs on TCP port 443. If this 
   is too open for you, email [support@duosecurity.com](https://wordpress.org/support/topic/php-errors-smooth-wall/support@duosecurity.com?output_format=md)
   for a list of IP ranges which your API hostname could change to.

Viewing 1 replies (of 1 total)

The topic ‘php errors – smooth wall’ is closed to new replies.

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## Tags

 * [login](https://wordpress.org/support/topic-tag/login/)
 * [php](https://wordpress.org/support/topic-tag/php/)

 * 1 reply
 * 2 participants
 * Last reply from: [Duo Security](https://wordpress.org/support/users/duosecurity/)
 * Last activity: [11 years, 8 months ago](https://wordpress.org/support/topic/php-errors-smooth-wall/#post-5274168)
 * Status: resolved