Some external email servers reject email with an error message "Other mail system problem 550-'Maximum line length exceeded (see RFC 5322 2.1.1).'"

Products

• Messaging Gateway

Issue/Introduction

Some emails are rejected by external servers with an error "Other mail system problem 550-'Maximum line length exceeded (see RFC 5322 2.1.1).'"

Resolution

Emails rejected by external servers could contain over 1000 characters (998 plus the carriage-return and line-feed) in one line. RFC 5322 2.1.1 states that the number of characters in a line must be no more than 998 characters. 

Please check if the setting of limit characters in a line in a mail client is set up appropriately.

Additional Information

2.1.1.  Line Length Limits