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Unable to Install – Fatal Error

Posted: June 17, 2013 at 2:06 pm

Rebekah Fedrowitz

June 17, 2013 at 2:06 pm

I am trying to install Event Espresso for the first time and am unable to.  I’m following the instructions on the website ( but receive a fatal error when I load.  This is the error I’m receiving:


Fatal error: Cannot redeclare postbox() (previously declared in /home2/nanporg/public_html/conference/wp-content/plugins/wordpress-plugin-for-1shoppingcart/es1sc-free.php:456) in /home2/nanporg/public_html/conference/wp-content/plugins/event-espresso/includes/functions/admin.php on line 199


What can I do to resolve this issue and install the program?  None of my add-on options (MailChimp, ticketing, etc) will install either.



Wordpress version: 3.5.1

Event Espresso Version: most recent – just purchased

New Installation (new customer)

Site is online.  No current registration page because revamping the site for another conference.  The URL is


  • Support Staff

June 17, 2013 at 2:16 pm

Hi Rebekah,

I’m sorry to hear about this. That’s no fun! Is it possible to deactivate the wordpress-plugin-for-1shoppingcart plugin?

Rebekah Fedrowitz

June 17, 2013 at 4:03 pm

I deactivated the 1ShoppingCart plug-in and Event Espresso installed correctly.  The challenge now is I cannot reactivate the 1ShoppingCart plugin for other products we sell.  Any way to work around this or I am going to have to choose one plug-in or the other?


June 18, 2013 at 5:30 am

Hi Rebekah,

There isnt a way around it currently without a code change in several files. I will raise a support ticket to get this amended in future versions of Event Espresso, to help reduce conflicts like this.

If you want to know which files to amend in the short term, please advise.

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