Mail Client Configuration
This page can turn on or off the automatic mail client
configuration URL for all virtual servers with email enabled.
Clients like Thunderbird can use this URL to detect SMTP
and IMAP settings based on only an email address, including
the correct username, port number and encryption type.
When enabled, a sub-domain named autoconfig is created
for each virtual server, and the URL path /mail/config-v1.1.xml
is mapped to a CGI that serves XML to supply the required
mail client parameters. These will be removed when the feature
is disabled.