Title: Plugin not compatible with wp 5.5
Last modified: June 26, 2021

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# Plugin not compatible with wp 5.5

 *  Resolved [bernchen7](https://wordpress.org/support/users/bernchen7/)
 * (@bernchen7)
 * [4 years, 11 months ago](https://wordpress.org/support/topic/plugin-not-compatible-with-wp-5-5/)
 * Hi
 * Been using your plugin across a few websites, primarily for gsuite customers.
   
   Awesome plugin and guide!
 * But i wish to highlight a unique situation in which the plugin causes a wordpress
   error for one site.
    The site is still under wp5.5 reason being that the theme
   used is no longer updated by theme author, updating the site to the latest version
   will render the site unuseable. I discovered only your plugin caused the error(
   i deactivated each plugin one by one)
 * The error i received is:
    include(/home/ksmassag/*URL hidden*/wp-content/plugins/
   wp-mail-smtp/vendor/composer/../../vendor_prefixed/guzzlehttp/psr7/src/MessageTrait.
   php): failed to open stream: No such file or directory in /home/*URL hidden*/
   wp-content/plugins/woo-discount-rules/v1/vendor/composer/ClassLoader.php on line
   444
 * Understood this is related to one plugin called woo discount rules but deactivating
   this particular plugin didn’t resolve the wp error.
 * Do u have any link to your previous versions that is suitable for wp5.5 use?
   
   The current i am using is 2.8 Thanks!
    -  This topic was modified 4 years, 11 months ago by [bernchen7](https://wordpress.org/support/users/bernchen7/).
    -  This topic was modified 4 years, 11 months ago by [bernchen7](https://wordpress.org/support/users/bernchen7/).
 * The page I need help with: _[[log in](https://login.wordpress.org/?redirect_to=https%3A%2F%2Fwordpress.org%2Fsupport%2Ftopic%2Fplugin-not-compatible-with-wp-5-5%2F%3Foutput_format%3Dmd&locale=en_US)
   to see the link]_

Viewing 3 replies - 1 through 3 (of 3 total)

 *  Plugin Author [Gregor Capuder](https://wordpress.org/support/users/capuderg/)
 * (@capuderg)
 * [4 years, 11 months ago](https://wordpress.org/support/topic/plugin-not-compatible-with-wp-5-5/#post-14598300)
 * Hi [@bernchen7](https://wordpress.org/support/users/bernchen7/),
 * I just checked and our plugin (v2.9.0 – latest version) does have the `.../vendor_prefixed/
   guzzlehttp/psr7/src/MessageTrait.php` file in it.
 * Do you have this issue with our latest version v2.9.0 or v2.8.0?
 * If it’s v2.8.0, please update to the latest version and let me know if that works
   OK. If it’s v2.9.0, please uninstall the plugin and install it again.
 * Maybe one of the files was not successfully created when you installed our plugin,
   and that’s why the missing file error is showing up?
 * Our plugin is compatible with WP version 4.9 and higher, so 5.5 should not be
   an exception.
 * Let me know how it goes.
 * Have a nice day!
 *  Thread Starter [bernchen7](https://wordpress.org/support/users/bernchen7/)
 * (@bernchen7)
 * [4 years, 11 months ago](https://wordpress.org/support/topic/plugin-not-compatible-with-wp-5-5/#post-14598409)
 * Hi, after updating and activating it, it still crashed.
    But i removed and reinstalled
   the latest version, it seems to work now. Will monitor and let u know if i run
   into it again. thanks for the tip!
 *  Plugin Author [Gregor Capuder](https://wordpress.org/support/users/capuderg/)
 * (@capuderg)
 * [4 years, 11 months ago](https://wordpress.org/support/topic/plugin-not-compatible-with-wp-5-5/#post-14601579)
 * HI [@bernchen7](https://wordpress.org/support/users/bernchen7/),
 * thanks for letting us know and I hope it works OK now 🙂
 * Have a nice day!

Viewing 3 replies - 1 through 3 (of 3 total)

The topic ‘Plugin not compatible with wp 5.5’ is closed to new replies.

 * ![](https://ps.w.org/wp-mail-smtp/assets/icon-256x256.png?rev=1755440)
 * [WP Mail SMTP by WPForms - The Most Popular SMTP and Email Log Plugin](https://wordpress.org/plugins/wp-mail-smtp/)
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 * 3 replies
 * 2 participants
 * Last reply from: [Gregor Capuder](https://wordpress.org/support/users/capuderg/)
 * Last activity: [4 years, 11 months ago](https://wordpress.org/support/topic/plugin-not-compatible-with-wp-5-5/#post-14601579)
 * Status: resolved