Getting Rid of the Vertical Line in Email you Reply To

(Outlook Express All Versions)
When replying back and forth in email, you may be adding a dark vertical line to your response each time. After several replies back and forth, this can cause quite a big indentation of a number of vertical lines. Here is how to prevent this from happening when replying in your html mail:

1. Click the Tools menu, Options
2. Click the Send tab
3. You’ll see an area called “Mail sending format”. Under that category,
click the HTML Settings Button
4. Deselect the checkbox for indent message on reply.

Instructions copied from: