eFeMail extension working fine with an error

Hello to everyone, I am succesful using eFemail extension for sending email with a GMail account.
The extension works and send regularly the mail and the attachment, but before the “OK” message i receive an “invalid argument” message.
I attach the JPG block.
Where is the problem ?

A post was merged into an existing topic: [ FREE ] eFeMail Auto Smtp Sender