Select this check box to use tracking tokens and to configure how they are displayed in the Subject line of the e-mail messages. Using tracking tokens increases the accuracy of determining if a new record is related to an existing, tracked record. When you change the e-mail prefix, up to 256 characters are saved as history. Long prefixes or too many prefix changes may cause lost data in history.
Increase or decrease the allowed size of files that can be attached to records.