Walter said:
I now use Outlook Express. My service provider has advised me that the reason
some of my messages are rejected is that the attachment is too large for this
email program.
I can switch over to Outlook - I have Office installed. Please advise
whether there is a limit to the size of a message plus attachement in Outlook
and - if so - what the maximum message size is.
Thank you.
The maximum message size is a quota defined by your e-mail provider.
Even if your e-mail provider allowed an infinitely sized e-mail, they
probably also have an anti-abuse quota that limits the length of a mail
session to N minutes, and that would expire because it takes time over a
limited bandwidth connection to transfer those bytes. If you use
dial-up or otherwise have a very slow connection to your mail server, a
huge-sized e-mail could take longer to transfer than your e-mail
provider allows for the max time of a mail session.
All e-mail gets sent as plain text. Yes, it ALL gets sent as plain
text. HTML-formatted e-mails are plain text with tags and directives
but those are also in plain text. RTF content gets encoded into a
plain-text part within the body of the e-mail (and looks like an
attachment to all e-mail clients other than Outlook which understands
RTF). Any file (other than text) that you attach to an e-mail gets
encoded into text characters inside a MIME part in the body of your
e-mail. It's all text that gets sent and why you can view its raw
source to see it.
The encoding used to convert binary content of attached files will
mushroom the size of that content. Converting to text takes more bytes
than those for the original binary file. You may only have under 5KB in
text characters for your message within an e-mail but a 10MB binary file
that you attach must get encoded into a text MIME part that can bloat
its byte size to 15MB, or more. The conversion to encode binary content
into text will increase the byte count significantly.
As you compose an e-mail, you can check on its current size. Save it
(Ctrl+S) which creates a copy in the Drafts folder. Then go look in the
Drafts folder to see its byte count in the Size column (add that column
if not already included in the view). If, say, your e-mail provider's
quota for max message size was 10MB, you could hit that after attaching
a 5MB to 7MB binary file.
Also, although the number of bytes is small, when you send
HTML-formatted e-mails, your message is duplicated. It will appear
TWICE inside the body of your message. One copy is the HTML copy (i.e.,
in an HTML MIME part). Another copy is the plain-text copy. This is
done so someone who uses an e-mail client that doesn't support HTML or
has it configured to read in plain-text only mode can still read your
message (they'll read the text version). A 100KB message will become
200KB+: 100KB for a text version of your message, another 100KB, at
least, for the HTML version of your message, and some more bytes for all
the MIME headers to delimit those versions in sections inside your
e-mail. This does NOT duplicate your attachments, just your message.
So with HTML-formatted e-mails that duplicate your message to include a
text and HTML version and with you adding a binary attachment that has
to get bloated in size to encode it into text characters in a MIME part
to delimit that content, what you thought would be under your
max-message-size quota could get exceeded.
