My setup: CiviCRM 5.18.3 on Drupal 7.
I created a Contribution batch. At transactions I chose two transactions of difference currencies e.g. HKD and USD and Assign them to a batch. Then I no longer be able to retrieve the list of batches because of fatal error: Dialog: DataTables warning: table id=crm-batch-selector-2 - Ajax error. For more information about this error, please see http://datatables.net/tn/7
In ConfigAndLog there are lines produced e.g. CRM_Core_Exception .... Invalid currency "HKD,USD" blah blah.....
Even I cancel the offending transaction it does not help. I had to delete the transaction in that batch to revive the batch's functioning.
Please kindly advise.
Best Regards,
2019-10-17 (too long to add to comments).
I copied this from ConfigAndLog, because no on-screen backtrace is shown even I enabled backtrace at System setting.
Oct 17 09:53:08 [debug] $backTrace = #0
/var/www/c53/web/sites/all/modules/civicrm/CRM/Core/Error.php(463):
CRM_Core_Error::backtrace("backTrace", TRUE)
#1 /var/www/c53/web/sites/all/modules/civicrm/CRM/Core/Invoke.php(55): CRM_Core_Error::handleUnhandledException(Object(CRM_Core_Exception))
#2 /var/www/c53/web/sites/all/modules/civicrm/drupal/civicrm.module(444): CRM_Core_Invoke::invoke((Array:3))
#3 /var/www/c53/web/includes/menu.inc(527): civicrm_invoke("ajax", "batchlist")
#4 /var/www/c53/web/index.php(21): menu_execute_active_handler()
#5 {main}