You might need to slow it down...
If the PDF is still being generated when the email is being created this might cause the error.
eror code 3 = Command is unavailable (for example, wrong operating system, wrong mode, etc.)
Thanks. I tried it, but that didn't solve the problem, even with a 30 second delay after PDF creation.
have you tried taking off the "no dialog" checkbox to see what email is being generated each time?
Also, have you considered setting up an SMTP account to serve this purpose? I've found the mail client can be tempermental for no apparent reason, since you're counting on an outside-of-filemaker program.
I actually use plugins (360works email) to do all my mailing, it's just more reliable.