NoReplyAll Outlook Add-In

The primary function is to add buttons to several of the Outlook ribbons to prevent people from doing a reply-all to your message, or forwarding it (using a facility built into Outlook & Exchange which is really lightweight compared to using IRM machinery, but which is not exposed in the existing UI). Additionally, it includes a check for email goofs such as omitting attachments or subject lines.

This works with Outlook 2007, 2010 and 2013 (32 or 64 bit), as long as you're using an Exchange account.

Download it from here: please take careful note of the installation instructions on that page.

A number of people have noticed that Outlook & Exchange offer hidden flags that let you specify if people are able to reply to or forward your email - for example, Scott Hanselman describes a neat little bit of VBA that lets you access some of them.

However, I wanted to have the current state of those flags reflected in the Outlook ribbon but wasn't able to achieve that with just VBA, so I applied the might of VSTO instead - complete overkill for twiddling two bits, but definitely easy to write and looks quite nice at the end of it all.

Add-in buttons When you install this thing, you'll see extra buttons at the end of the ribbon on the email composition window. Clicking on the buttons will prevent recipients of your emails from performing a reply to all, forward or reply to anyone. Clicking again toggles the relevant option's state back again.

Normally, the actions are enabled for new messages and meeting requests, but you can set the default state to be disabled via the add-in's options page.

The corresponding button on ribbons of the mail viewing window and the Outlook main window (the latter only in Outlook 2010 and 2013, since Outlook 2007 does not have a ribbon on the main window) show the state for received messages and will let you re-enable the reply all, etc. options. Or to disable them should you want to do that - in fact, another facility available for people worried about ever accidentally replying to all is to disable reply all for all received messages - see the options page again.

Note that the email recipient does not need to have this add-in installed to have reply all disabled: the flags I mentioned are handled by Outlook and Exchange - as long as the sender and recipient are attached to the same Exchange servers, the flag settings get passed along; and if the recipient is using the Outlook desktop client, the flag setting will be honoured. Of course, the recipient could use the add-in to re-enable reply all! (If the recipient is using some other tool to read email, or is not on the same Exchange system, the flags are ignored.)

As I said above, this is a lightweight means of limiting the propagation of emails - it's also very weak, which I hope I've emphasised by making it easy for recipients to re-enable any facility that the sender had disabled! (It is actually very easy to re-enable them without having the add-in; I'm really not making things "less secure" here.) If you do want a mechanism for protecting your emails robustly and much more securely, take a look at the IRM facilities that Exchange offers.

And just because I could, I added an extra bit of functionality to warn you if you send an email with a blank subject line - since that's built into Outlook 2010/2013 this is only active in Outlook 2007. After doing that, I got a bit carried away and included a detector for missing attachments when you send an email (this is for 2007 and 2010, since Outlook 2013 includes similar functionality) - you can create a list of keywords (such as "attached" and "attachment" - whatever terms you're likely to use) on the add-in's options page; then, when you send an email containing one of those words, the add-in will check to see if there are attachments and warn you if not. Actually, the mechanism is slightly more sophisticated: there are two lists, the second intended to be contexts in which the keywords should be ignored (such as legalese in your email signature), so the rule is "issue a warning if any of the words in the first list appear unless they also match something in the second." The add-in attempts to distinguish between embedded images and other attachments so, for example, an email signature with an image shouldn't trick the tool into thinking an attachment is already present.

That context can be specified as a regular expression, allowing for more sophisticated rules. For example, the regular expression "(?m)^\s*> .*" will cause everything on a line starting with "> " to be ignored, and "(?s)(^|\n|\r)From: .*$" will cause everything including and following a line starting with "From:" to be ignored. Both of these are common patterns in email threads... They can be combined into a single regular expression as:

((?m)^\s*>.*)|((?s)(^|\n|\r)From: .*$)

No, a cat did not walk over the keyboard just then. See the MSDN documentation if you want to get a better understanding of regular expression syntax.

(This add-in isn't really related to the Research Desktop project, but sort of fell out of early investigations into the VSTO technology used in Research Desktop.)

If you want to find out how the thing works, I've written a series of blog posts on the technology behind this add-in.

Please use the Research Desktop forum or the blog for problem reports or any other comments about the tool.