Problem with Email Log

I'm trying to troubleshoot situations where my emails are not being sent from the component.

I look at the Email Log, and the emails are shown. However, if I click on one of the emails I get:

An error has occurred.

0 Class "ToolbarHelper" not found

 Return to Dashboard

Should I be able to view the outgoing email?

Thanks
Andy

I'm seeing this exact same issue. Is there a simple solution to share?