Sent faxes are rejected because the message size is too large - Solution 1


The sender of the fax email requests receives a non-delivery report e-mail message stating that the email is too large.  The following are sample NDR messages :

This message is larger than the current system limit or the recipient's mailbox is full. Create a shorter message body or remove attachments and try sending it again.
<server.domain.local #5.2.3 smtp;450 5.2.3 Msg Size greater than allowed by Remote Host>


Delivery has failed to these recipients:
This message exceeds the maximum size allowed.
550 5.2.3. RESOLVER.RST.SendSizeLimit; message too large for this sender


  • GFI FaxMaker
  • All supported environments


Remove the check boxes on the SMTP message size limits in the Default SMTP virtual server of IIS on the GFI FaxMaker server
  1. Open the Internet Information Services (IIS) Manager
    • If GFI FaxMaker is installed on Server 2008 or later, it should list in All Programs as: Internet Information Services (IIS) 6.0 Manager
  2. Right click the SMTP Virtual Server and select Properties
  3. Navigate to the Messages tab and remove checks to limit sizes, with primary focus on Limit message size
    • The default message size is set to a 2MB when SMTP is initially installed
  4. Restart IIS via command prompt by typing 'iisreset' and pressing [ENTER]


Message size limitations are set in Exchange or on the SMTP virtual server of IIS on the GFI FaxMaker server (If on a separate machine than Exchange)