Not working in D7, sends no emails.

Hi, I have been testing broadcast with webform 7.x-3.20.

On sending a broadcast message, I see no error. No errors in the watchdog either. Also no emails are sent out the submissions
Then, send a second braocast, back-to-back, and I get the error below

Fatal error: Call to undefined function dpm() in C:\inetpub\wwwroot\drupal_XXXX\sites\all\modules\webform_broadcast\webform_broadcast.module on line 122

I'll have a little time to look at this today.