Currently, Guard attaches help files (in each language of the recipients) that will get displayed if they do not have PGP clients. It notifies them that they received a PGP email, and that they should log onto the UI to read the email.
Some clients are having trouble with this file, and it was requested that we provide an option to turn this off.

Configuration added


# Option to attach help files to outgoing PGP emails. The help files will not
# be displayed in PGP enabled email clients, rather they will only be displayed
# for clients that don't have PGP, and will explain to them that this is a PGP email
# and that they should log onto the UI to read the email
com.openexchange.guard.attachHelpFile=true