Title: Pro version serial doesn't activate
Last modified: August 22, 2016

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# Pro version serial doesn't activate

 *  Resolved [ClueyKid](https://wordpress.org/support/users/clueykid/)
 * (@clueykid)
 * [11 years, 2 months ago](https://wordpress.org/support/topic/pro-version-serial-doesnt-activate/)
 * Hi, I just paid for the pro version, but entering my serial and hitting save 
   I get the following error:
 * Fatal error: Class ‘IXR_Client’ not found in /my wordpress install path/wp-includes/
   class-wp-http-ixr-client.php on line 9
 * Have you seen this before?
 * [https://wordpress.org/plugins/wp-retina-2x/](https://wordpress.org/plugins/wp-retina-2x/)

Viewing 8 replies - 1 through 8 (of 8 total)

 *  Plugin Author [Jordy Meow](https://wordpress.org/support/users/tigroumeow/)
 * (@tigroumeow)
 * [11 years, 2 months ago](https://wordpress.org/support/topic/pro-version-serial-doesnt-activate/#post-5868381)
 * Hello!
 * It seems there was a glitch since yesterday, when I added proxy support. I did
   another update today and it should work. Can you try again?
 *  Thread Starter [ClueyKid](https://wordpress.org/support/users/clueykid/)
 * (@clueykid)
 * [11 years, 2 months ago](https://wordpress.org/support/topic/pro-version-serial-doesnt-activate/#post-5868383)
 * Yep – an update fixed it. Thankyou!
 *  Plugin Author [Jordy Meow](https://wordpress.org/support/users/tigroumeow/)
 * (@tigroumeow)
 * [11 years, 2 months ago](https://wordpress.org/support/topic/pro-version-serial-doesnt-activate/#post-5868389)
 * Super 🙂 Thank you too!
 *  [Balafononlus](https://wordpress.org/support/users/balafononlus/)
 * (@balafononlus)
 * [11 years, 2 months ago](https://wordpress.org/support/topic/pro-version-serial-doesnt-activate/#post-5868426)
 * Please I have this problem when I login
 * Warning: Cannot modify header information – headers already sent by (output started
   at /home/bantousb/public_html/wp-content/themes/fragrance/functions.php:20) in/
   home/bantousb/public_html/wp-includes/pluggable.php on line 1179
    can you help
   me please thank you very much
 *  [Balafononlus](https://wordpress.org/support/users/balafononlus/)
 * (@balafononlus)
 * [11 years, 2 months ago](https://wordpress.org/support/topic/pro-version-serial-doesnt-activate/#post-5868432)
 * Warning: Cannot modify header information – headers already sent by (output started
   at /home/bantousb/public_html/wp-content/themes/fragrance/functions.php:20) in/
   home/bantousb/public_html/wp-login.php on line 431
 *  Plugin Author [Jordy Meow](https://wordpress.org/support/users/tigroumeow/)
 * (@tigroumeow)
 * [11 years, 2 months ago](https://wordpress.org/support/topic/pro-version-serial-doesnt-activate/#post-5868435)
 * Have you tried the new version today?
    Did you check your PHP logs?
 *  [Balafononlus](https://wordpress.org/support/users/balafononlus/)
 * (@balafononlus)
 * [11 years, 2 months ago](https://wordpress.org/support/topic/pro-version-serial-doesnt-activate/#post-5868454)
 * Thank you very much for your help, I don’t manage to login when I put my usermaname
   and password i receive this message :
    Warning: Cannot modify header information–
   headers already sent by (output started at /home/bantousb/public_html/wp-content/
   themes/fragrance/functions.php:20) in /home/bantousb/public_html/wp-login.php
   on line 418
 * Warning: Cannot modify header information – headers already sent by (output started
   at /home/bantousb/public_html/wp-content/themes/fragrance/functions.php:20) in/
   home/bantousb/public_html/wp-login.php on line 431
 *  Plugin Author [Jordy Meow](https://wordpress.org/support/users/tigroumeow/)
 * (@tigroumeow)
 * [11 years, 2 months ago](https://wordpress.org/support/topic/pro-version-serial-doesnt-activate/#post-5868455)
 * Sorry Balafononlus but actually how is this linked to the plugin or even the 
   current discussion? I am not sure…
 * If you think it’s related please create a new discussion and give more details,
   those warnings don’t mean much unfortunately. Check your PHP logs and if you 
   think it’s the plugin delete it by FTP. If the problem is still there track for
   the plugin with this pb.

Viewing 8 replies - 1 through 8 (of 8 total)

The topic ‘Pro version serial doesn't activate’ is closed to new replies.

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## Tags

 * [activate](https://wordpress.org/support/topic-tag/activate/)
 * [pro](https://wordpress.org/support/topic-tag/pro/)
 * [serial](https://wordpress.org/support/topic-tag/serial/)

 * 8 replies
 * 3 participants
 * Last reply from: [Jordy Meow](https://wordpress.org/support/users/tigroumeow/)
 * Last activity: [11 years, 2 months ago](https://wordpress.org/support/topic/pro-version-serial-doesnt-activate/#post-5868455)
 * Status: resolved