Add one or more attachments to the email. You can specify multiple attachments using expressions that can be resolved while running a mail merge process. In the screenshot you see 3 attachment expressions, with a 4th being added.

1. Select a file or construct one dynamically using Expressions
2. Press [Add] to include it as expression.
[SelectFile] lets you decide which file to include when running saved mail merge processes. SelectFileOnce will ask only once if you run the process on multiple records.
