Formbuilder 0.7.3 generates smtp error when sending e-mail

[BaukeJ]

Recently I have encountered some problems with FormBuilder (the 0.7.3. version). I never encountered this problems before with this module and have been using the page it concerns for some time, without problems.
I have been using the module on several places, including http://baukejonkmans.nl/contact.html
When submitting this form, formbuilder generates an error such as:

Sorry! Er is een fout opgetreden tijdens de formulierverwerking.
SMTP Error: The following recipients failed:{mail 1}
SMTP Error: The following recipients failed: {mail2}

Because I understand your Dutch is a bit rusty,in the first sentence it says

Sorry, an error has occured while processing the form.

To be more clear: in this case the {mail1} adres is the adress of the person submitting the form. The {mail2} adres is the e-mailadress that i have set as recepient of the e-mail.
I have read your troubleshooting in the help section of the module and tried all the things it says.

After this I checked my SMTP settings with my hostingprovider, changed the e-mail and password several times and off course checked it. The strange thing: sending e-mail does work with CMSmailer and other applications that use e-mail, like eventsmanager, but not with your formbuilder. Also testing in CMSmailer works.

As a last resort I have completely reinstalled the module. Unfortunately it doesn't seem to work.

Can you help me? I work with CMSMS 1.11.10

[velden]

The error itself seems to come from the SMTP client/server.

I just successfully sent the form to you using your email address.

Probably the SMTP server does not allow unknown sender address (it could check for domain or even the existence of the email address on the server).

You could try to configure another method in CMS Mailer and try again. Else you should configure form builder to NOT use the visitors address as the sender address (use it only as reply-to address if possible).