No error message is displayed when creating an issue when an error occurs due to a field configuration problem.
# Attempt to create an issue while a field is required but will be present on the issue collector (eg. Assignee is set to Required)
# Fill out all fields correctly
# Submit (Page will refresh, and show issue collector configuration page again as it was not submitted)
The red box error is not shown until an element on the page is changed. Changing the issue type for the issue collector will make the error message appear at the top of the page.
JIRA Server 7.8