I came across this, but it doesn't really do what I want:
When you reply to a message in Outlook 2007 and 2010 (and probably older and newer versions), it inserts a light blue horizontal line just above the message you're replying to. This line is different than the ones you can create with
Insert > Horizontal Line in that it can't be manipulated. You can cut it out by selecting a range of text, but, when you paste, it disappears. I want to emulate this line exactly.
The reason why is because I am compiling a convoluted message thread into a summarized thread before I forward it out to the recipients. The OCD part of me wants it to be exactly the same as the reply separator.
Update: In looking at an email's source code, the horizontal line is apparently a
<div> with a top border:
<div><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'></div></div>
How to get this into my Outlook 2007 email is a chore, though. There is apparently a tool that let you edit an email source code directly, but it only works for 2010 and 2013. I've also found that I can save an email's source as an HTML file, edit it, and then attach it as text, but editing an email's HTML in a text editor while conforming to the HTML document structure of Outlook is quite a chore, so I'd rather not do that.