Does Exchange 2010 impose a maximum length for individual headers? If so, what is it?
Let's say a user sends an email to 200 recipients, resulting in a TO: field having 200 email addresses (very bad idea I know). Or let's say an upstream content filter adds an X-header that has a lot of information.
At what point would Exchange reject the message. Would it reject the message?
The reason I ask is because I've seen other MTAs have issues with large headers and am curious about Exchange. For example, by default, SendMail milter communication fails if a single header is larger than 64K (as per http://ftp.sunet.se/pub/unix/mail/sendmail/KNOWNBUGS).