.APPT File

The appt file extension was in the past used for a specially protected PowerPoint presentation encrypted using the Authentica Secure Office.

Seems like old product as the developer and its product portfolio was acquired by EMC Corporation. Probably known by another name now.

This appt file type entry was marked as obsolete and no longer supported file format.

This type of file is no longer actively used and is most likely obsolete. This is typically the case for system files in old operating systems, file types from long discontinued software, or previous versions of certain file types (like documents, projects etc.) that were replaced in higher versions of their original programs.

How to open:

You can access these files using Authentica Secure Office.

How to convert:

Probably cannot be converted to other formats.