Title: Internal Server Error checking out
Last modified: March 22, 2021

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# Internal Server Error checking out

 *  Resolved [bmw2182](https://wordpress.org/support/users/bmw2182/)
 * (@bmw2182)
 * [5 years, 2 months ago](https://wordpress.org/support/topic/internal-server-error-checking-out/)
 * We get an internal server error upon checking out. The order does go through,
   but the customer doesn’t realize it, because they get this error message and 
   never get the confirmation email. I turned on the debugging and get the following
   information:
 * CRITICAL Uncaught Error: Call to undefined function PHPMailer\PHPMailer\ctype_alnum()
   in /hermes/bosnacweb07/bosnacweb07ap/b287/ipw.musicali/public_html/WordPress/
   wp-includes/PHPMailer/PHPMailer.php:1793
 * I’m not sure how to resolve it. HELP
 * The page I need help with: _[[log in](https://login.wordpress.org/?redirect_to=https%3A%2F%2Fwordpress.org%2Fsupport%2Ftopic%2Finternal-server-error-checking-out%2F%3Foutput_format%3Dmd&locale=en_US)
   to see the link]_

Viewing 6 replies - 1 through 6 (of 6 total)

 *  [cjhill](https://wordpress.org/support/users/cjhill/)
 * (@cjhill)
 * [5 years, 2 months ago](https://wordpress.org/support/topic/internal-server-error-checking-out/#post-14220438)
 * Try turning off Low Stock notifications in WooCommerce. I had this problem and
   switching these off along with removing low stock/out-of-stock thresholds fixed
   this.
    It was something to do with an error being generated when it tries to 
   send the stock notification email to you.
 *  Plugin Support [Gabriel – a11n](https://wordpress.org/support/users/gabrielfuentes/)
 * (@gabrielfuentes)
 * [5 years, 2 months ago](https://wordpress.org/support/topic/internal-server-error-checking-out/#post-14220618)
 * Hi there 👋
 * This kind of problem is usually caused by a conflict with your theme or with 
   another plugin.
      The best way to determine this is to:
    - Temporarily switch your theme to [Storefront](https://www.woocommerce.com/storefront/)
    - Disable all plugins except for WooCommerce
    - Repeat the action that is causing the problem
 * If you’re not seeing the same problem after completing the conflict test, then
   you know the problem was with the plugins and/or theme you deactivated. To figure
   out which plugin is causing the problem, reactivate your other plugins one by
   one, testing after each, until you find the one causing conflict. [You can find a more detailed explanation on how to do a conflict test here.](https://docs.woocommerce.com/document/how-to-test-for-conflicts/)
 * **Before you start**
    1. First, please make sure you have a good backup in place of your full site and
       database. Most hosting companies have this included in the subscription, but
       you could also consider using a service like Jetpack. If something goes wrong,
       it’s nice to know that you can restore your site.
    2. Second, I would suggest installing a plugin called Health Check & Troubleshooting.
       This is a plugin developed by the WordPress community and it allows you to disable
       plugins without affecting your current site visitors.
 * I hope that helps!
 *  Thread Starter [bmw2182](https://wordpress.org/support/users/bmw2182/)
 * (@bmw2182)
 * [5 years, 2 months ago](https://wordpress.org/support/topic/internal-server-error-checking-out/#post-14220751)
 * I switched to the Storefront theme, disabled all the plugins except for WooCommerce
   and Square. I need the square to enter the payment info to get the error message.
   I’m still getting the same error. Any other thoughts?
 *  Plugin Support [Gabriel – a11n](https://wordpress.org/support/users/gabrielfuentes/)
 * (@gabrielfuentes)
 * [5 years, 2 months ago](https://wordpress.org/support/topic/internal-server-error-checking-out/#post-14226125)
 * Thank you for running the test.
 * It sounds like this issue is directly related to the **WooCommerce Square** plugin.
 * So in this case, I would like to recommend you to reach out to us regarding this
   specific issue on the following support forum:
 * [https://wordpress.org/support/plugin/woocommerce-square/](https://wordpress.org/support/plugin/woocommerce-square/)
 * Please kindly note that this particular forum is for questions that are directly
   related to the features and functionality of the free WooCommerce plugin.
 * Cheers 🙂
 *  Plugin Support [Gabriel – a11n](https://wordpress.org/support/users/gabrielfuentes/)
 * (@gabrielfuentes)
 * [5 years, 2 months ago](https://wordpress.org/support/topic/internal-server-error-checking-out/#post-14257029)
 * Since it’s been a while since we last heard back from you, I’m going to mark 
   this thread resolved.
 * Hopefully, you were able to find a solution to your problem! If you have further
   questions, please feel free to open a new topic.
 * Cheers! 🙂
 *  Thread Starter [bmw2182](https://wordpress.org/support/users/bmw2182/)
 * (@bmw2182)
 * [5 years, 2 months ago](https://wordpress.org/support/topic/internal-server-error-checking-out/#post-14258821)
 * It is still not resolved. I posted in [https://wordpress.org/support/plugin/woocommerce-square/](https://wordpress.org/support/plugin/woocommerce-square/)
   like I was asked to, and no luck 🙁

Viewing 6 replies - 1 through 6 (of 6 total)

The topic ‘Internal Server Error checking out’ is closed to new replies.

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 * 6 replies
 * 3 participants
 * Last reply from: [bmw2182](https://wordpress.org/support/users/bmw2182/)
 * Last activity: [5 years, 2 months ago](https://wordpress.org/support/topic/internal-server-error-checking-out/#post-14258821)
 * Status: resolved