"system.exception:index was out of range. Must be non-negative and less than the size of the collection" when importing CSV contact list in SendSuite Live

Learn how to resolve the error "system.exception:index was out of range. Must be non-negative and less than the size of the collection" when importing a CSV contact list into SendSuite Live.
Products affected: SendSuite® Live

Issue

When attempting to import a CSV contact list using the import option in the  Address Book, the following error is displayed:
 
"system.exception:index was out of range. Must be non-negative and less than the size of the collection. Parameter name: index' displays after providing a list name, description, selecting the file and importing under the outlook file type."

Cause

CSV or Excel files can only be imported under the custom file type in the import dialog menu.

Resolution

Re-import the file using the custom method for this file type.

UPDATED: June 03, 2021