Go to Site > Settings > User Imports, and scroll down to the User Import Notifications section.  When the Import Feedback box is marked, any email address listed under Email Recipients will receive an automated email after each import showing success or failure and details.  To add additional email addresses, click Add Another link under the Email Recipients box, enter the email address of the system user to receive notifications, and then click the green Update Settings button.

It is vital that at least one System Administrator, and if possible at least one IT Administrator, receive these notifications in order to assist in the changes required for the import to be successful.  The following messages may appear on these failure notifications:

 
Error Message #1
[ERROR] AWS::S3::Errors::NoSuchKey No Such Key 
[ERROR] Net::OpenTimeout execution expired
[ERROR] TypeError no implicit conversion of Array into String
 
Email text: 
The file has failed and no rows have been imported. Please try again or reach out to our support team to determine the source of the issue.
 
 
Error Message #2
[ERROR] CSV::MalformedCSVError Missing or stray quote in line 3329
 
Email Text:
The file has failed due to a missing or stray quote in the listed line.  Please investigate the source of the import file data and remove the quotation marks.
 
 
Error Message #3
[ERROR] CSV::MalformedCSVError Unquoted fields do not allow \r or \n
 
Email Text 
The file has failed due to a line break not within a quotation mark.  Please check the file and reimport.
 
 
Error Message #4
For [ERROR] RuntimeError No Rows Imported
 
Email Text 
The Import file has failed and no rows have been imported.  Please reach out to our support team to determine the source of the issue. 
 
If you are unsuccessful correcting any of the errors, or would like additional information, please contact Customer Support for assistance.