"Allow email addresses to start with a dash" option was removed from Symantec Messaging Gateway (SMG) 10.6.2. According to online Help for Protocols > Settings the option is still present.
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Currently (10.6.2+) the option "Allow email addresses to start with a dash" is not available and dash symbols are not allowed as first characters of email address. This option is currently being further evaluated for inclusion at later time.
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