Why Can't I Edit a Previously Created Notification Transmittal?

The intent of the notification transmittal is to act as an email announcement, sent from within Viewpoint For Projects™, that contains attachments from other areas of the enterprise. Renaming/revising a notification transmittal would be similar to changing the subject or content of an email after it was sent.

For expanded functionality where you can edit and revise previous items, give matrix transmittals a try.