[IMail Forum] Something new on malformed headers

[IMain Admin at BC Web]

OK, I'm sure by now everyone's tired of hearing me talk about "invisible messages", but if you use IMAP for client access, this is a very critical issue.  So each time I discover something new, I throw it up here, hoping that someone more knowledgeable than I can make sense of it.   I've been playing with the headers of the "invisible" messages.  That is, I went to the main.mbx file and located a message that I know will not download into Outlook Express.  Then I made small changes to the header file until I figured out which things "break" the message (make it invisible).  Here's what I found:   The From:, To:, and CC: lines are often written in the format: "display name" <mailbox@domainname>   For example, and message to me might have To: "Ben Bednarz" <[EMAIL PROTECTED]>   Apparently, OE can choke on some punctuation symbols that are embedded in the display name.  For example, by far and away the most common problem I have found is display names that use "lastname, firstname".  Another example:   To: "Bednarz, Ben" <[EMAIL PROTECTED]>   Some other punctuations can also cause "invisibility."  For example, I found a bad message of the format:   To: "Ben Bednarz \(email\)" <[EMAIL PROTECTED]>   Presumably the sending mail client added the backslashes ("\") as "escape" characters for the parenthesis.  However, those backslashes cause OE to chock.  If I remove the backslashes, then the message will download & display corrected as:   To: "Ben Bednarz (email)" <[EMAIL PROTECTED]>   One of the strange things is that the bad characters (, \, etc.) are only a problem when the display name is contained in double-quotes.  Get rid of the double-quotes, and the message will download  & display just fine.  For example, both of the following work fine:   To: Bednarz, Ben <[EMAIL PROTECTED]> To: 'Bednarz, Ben' <[EMAIL PROTECTED]>   Although I think you do get some funny display results when using the comma without quotes (but the message will display!).   You can also get an invisible message from strange characters in your subject line.  For example, I had a message from Intel that wouldn't download because they had included a registration mark (the R inside a circle) in the subject line.  It displayed correct in Notepad when I was looking at the main.mbx file, but it wouldn't download to OE.   So now I know what in the message headers causes the problem, I just have to figure out how to fix it.   My first question is: Is the formatting of the header From:, To:, Cc:, and Subject: lines set by the sending mail client, or could is it changed at all by the mail servers?  In particular, could my IMail server change those parts of the mail header?   Ben Bednarz