The LDAP/X.500 pop-up addressing form allow users, from within PMDF MAIL or VMS MAIL, to obtain e-mail addresses from an LDAP directory or an X.500 directory via an LDAP server. They can search both the local directory and any other remote directories accessible via the network. For a site connected to the Internet, this means that the global X.500 directory is accessible.

With the terminal-based form, designed to run on terminals supported by the SMG$ run-time library, users can also change the e-mail address or password associated with their entry in the directory.

The form is included with the base PMDF package and can therefore be used on any node on which PMDF and a TCP/IP package is installed. In particular, its use is not limited to just a node on which the LDAP or X.500 directory is installed; they can be used on any node which has TCP/IP access to a (possibly remote) LDAP server.