Greg Welch, an Associate Professor in Computer Science at UNC, Chapel Hill, has written a nifty plugin for Mail.app that allows you to “follow up” or send subsequent thoughts to all the recipients of an email more easily and naturally.
He found that he often wanted to send an afterthought or important observation to an email after his initial reply. Mail’s default “Reply All” function only places only the original sender’s email address into the To: field, skewing the emphasis in a group conversation.
His plugin adds a “Followup” commands to Apple Mail’s Message and Contextual Menus, so that the To, Cc: and Bcc: addresses appear in the reply exactly as they appeared in the original message:
Scott Morrison, the developer of Mail Act-on and MailTags, also contributed some code and advice to the project.
Installation instructions and the offer of email support for the plugin can be found on Greg’s web site 
as can the plugin itself.
For me, Mail.app won’t launch with the bundle installed.
Hmmm… That’s bad. It worked fine for me just fifteen minutes ago.
That’s not a very helpful thing to say, perhaps, but it shows that there is hope.
I’d drop Greg an email in the first instance and let him know in case it is a problem that might affect a lot of people.
What other plugins do you have installed?
(From Greg, the apologetic MailFollowup developer) My apologies folks. I did test it with several people, but unfortunately a bug got through that affected people who do NOT have the Mail Act-On plugin installed. I have released a new version (1.0.1) and had positive reports. Again, sorry about that.
Works now. Thanks
That will teach people not to have Mail Act-on installed ;-)
Seriously, that’s a fantastic response time on the fix, Greg.
in your screenshot on the mailfollowup web page of Mail.app, what is it that allows you to have tabs in Mail.app??? Thanks!
It’s Adobe GoLive running in the background. No spectacular or sexy Mail alteration. Sorry. (Poor screenshot. I should fix/redo it.)
Is the difference between MailFollowup and Mail’s built-in Send Again that the former creates a “quoted” draft of the selected message?
Yes. MailFollowup is effectively a “Reply All” that keeps the To, Cc, and Bcc lists the same as the original message (as “Send Again” does).
Thanks, Greg. If I’d noticed your reply to that question on VersionTracker a few minutes sooner I wouldn’t have asked it again here. :-)
Great plug in. Any chance of making the Follow Up action as a button for the toolbar? I tend to go and hit reply in the toolbar and start editing the email before realising that FollowUp is installed hehe.
It’s a nice idea. Why not ask Greg
?
I would love to have a toolbar button. Unfortunately it seems it’s non-trivial to do in a Mail bundle. It would be great to find the source code for a simple example, or someone to help, but I haven’t found that yet. Any volunteers? :)
A toolbar button is coming soon to a version 1.1 near you….
I’m sorry but I just can’t see any difference between choosing Reply All and Followup. I’ve tested this on a variety of emails with to’s, cc’s and bcc’s and whether I press Reply All or the new Followup button, the resulting replies look the same. Can someone help me see what the benefit of this is? Thanks.
(from the developer)
I’ve been trying to post a response, but keep getting an error. Tim is checking on it, but I wanted to try a simple short post, like this….
–greg
(from the developer)
Hello Rick.
A “Followup” is in some sense a combination of Reply All and Send Again. Like Reply All it quotes the original message and subject. Like Send Again it keeps the recipients fields identical (in most cases) to the original message, which Reply All does not do. (Reply All goes to the original sender only, and cc’s all the others.) Another person has likened it to a “Forward All” which is not a bad description, although not quite right.
Take care,
–greg
Excellent!!
Hmmm… Yes, an odd one. Sorry about that. I’ll take the two preceding comments out. Looking forward to the chance of posting about Leopard FollowUp!
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