XF 1.4 Strange Error on registration

[Dacon]

Recently when a user registers on my forums it says
"A server error has occurred, please try again later" Although it'll still create their account

The error log is

#0 /home/admin/public_html/minevast_com/community/library/Zend/Db/Statement.php(297): Zend_Db_Statement_Mysqli->_execute(Array)
#1 /home/admin/public_html/minevast_com/community/library/Zend/Db/Adapter/Abstract.php(479): Zend_Db_Statement->execute(Array)
#2 /home/admin/public_html/minevast_com/community/library/Zend/Db/Adapter/Abstract.php(574): Zend_Db_Adapter_Abstract->query('INSERT INTO `xf...', Array)
#3 /home/admin/public_html/minevast_com/community/library/XenForo/DataWriter.php(1624): Zend_Db_Adapter_Abstract->insert('xf_user', Array)
#4 /home/admin/public_html/minevast_com/community/library/XenForo/DataWriter.php(1613): XenForo_DataWriter->_insert()
#5 /home/admin/public_html/minevast_com/community/library/XenForo/DataWriter.php(1405): XenForo_DataWriter->_save()
#6 /home/admin/public_html/minevast_com/community/library/XenForo/ControllerPublic/Register.php(404): XenForo_DataWriter->save()
#7 /home/admin/public_html/minevast_com/community/library/XenForo/FrontController.php(347): XenForo_ControllerPublic_Register->actionRegister()
#8 /home/admin/public_html/minevast_com/community/library/XenForo/FrontController.php(134): XenForo_FrontController->dispatch(Object(XenForo_RouteMatch))
#9 /home/admin/public_html/minevast_com/community/index.php(13): XenForo_FrontController->run()
#10 {main}

If anyone knows what causes this or how to fix this, help would be greatly appreciated!

 

[Mike]

You've chopped off the actual error message. It's above what you pasted into your message.

 

[Dacon]

You've chopped off the actual error message. It's above what you pasted into your message.

Oh my bad, here's the top part:

Zend_Db_Statement_Mysqli_Exception: Mysqli statement execute error : Duplicate entry 'snipecraft' for key 'username' - library/Zend/Db/Statement/Mysqli.php:214

 

[Mike]

That would seem to imply a race condition, which would require the request to be submitted twice in rapid succession. It seems unlikely for this to be happening with any consistency unless there's something else interfering and automatically resubmitting the request unexpectedly.