If you have ever wondered why this line is of exactly the (strange) color it is in Outlook Express, here's the answer: the indentation line is drawn in the color of your default font for emails.
To change the color of the quotation line in Outlook Express:
- Change the color of the default font.
While this is the only place where you can change the line color, you're free to set the font color of your reply to whatever you like manually while composing a message in Outlook Express. If your default font color is red, for example, the line will be red even if you change the font color to blue in your reply.