We have used Faxmail.com to send fax (Email to fax) from one of our ASP.NET application, and it has been working from ages, suddenly its failing to send fax if the file size is more than 250 KB. We have been sending fax with file size up to 8 MB with same application before.
Eg :[email protected]
Send the email message from SMTP to the desired fax user and it used to deliver to fax machine.
SmtpClient smtp = new SmtpClient();
MailMessage nm = new MailMessage();
smtp.Host = "smtp.domain.com";
smtp.Send(nm);
We don't see any exceptions while sending email, however its not reaching fax machine (receipient).
Note :- This was been working since early 2000.
We found the issue was at the easylink server which is the service provider for faxmail.com. Easylink was failing to render the PDF attachment that was being sent. Upgrading the server with latest PDF patch resolved the issue.