Use Extension to specify the application to use when viewing attachments of a particular file type. When you receive an attachment, GroupWise attempts to open the application associated with the attachment's extension.
Click Tools > Options.
or
In Macintosh, click GroupWise > Preferences.
Click Extension.
Click Add to add a viewer application for particular kinds of files. Type the path and name of the external application, or browse to its location. Type the file extension (such as .txt or .doc, with no leading dot) in the Extensions box. Click OK.
Click Use Application to Open Other Files to use the system default application to open other file types. If you want to use another application, click Custom Application, then type the path of the application.