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I notice that recent emails from gmail come with some sort of automated final line of the style


One specific example I just got is this:


I also notice, and can repeat this, that when I reply to this message with my mail client (alpine 2.00 OSX) it says it is sending the message and then times out with the message:

Waited 15 seconds for server reply.  Break connection to server [Y/N]? 

And when I press Y it says:

[>Mail not sent. Sending error: 421 SMTP connection broken (reply)<]

If I delete the hex code from the bottom of the message I am replying to, my reply is sent without a problem.

Does anyone know what this weird hex-ish signature is? And why is it stopping me from sending mail unless I delete it?

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One solution seems to be to set option [X] Prefer Plain Text in the alpine preferences. – user31752 Sep 21 '10 at 1:06

It's probably a mime boundary. A MIME message can contain more than one part, with a line like this splitting each part. Wikipedia has a good explaination

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