SMTP Security Profile Error 500

Hi people.

 

I have a SMTP Virtual Server with Startls. Under this VS i applied a Security Profile SMTP by default with all options of "Defense Configuration" without check (alarm and block). Well, the mails of one of us customers has been blocked by F5. The customer receive an undelivered mail indicating "Error 500 command unrecognized". I verified the security profile SMTP and all options are without check. I enabled "alarm" under option SMTP COMMAND and inmediatly when the client try to send me an email the F5 shows this message: Unknown Method!

 

I tried to place the commands VRFY,EXPN and ETRN as allowed but the mails continue to be blocked. I do not understand why they are blocked if the policy is not blocking anything. I only receive the emails when I disassociate the virtual server policy. What can I do about it to maintain the policy without blocking the client's mails?