Email will send both plain text and HTML. A plain text renderer will usually be displayed in a monospaced font, but there is no guarantee. More importantly, you cannot do anything to change which font will be displayed in clear text.
If your recipient reads mail in an HTML-enabled mail client, you can do this by wrapping the <font face="Courier New, Courier, monospace"></font> (font tag) around the parts of the letter that you would like to have in Courier . In the proposed method, you just have to:
text = '<font face="Courier New, Courier, monospace">' + text + '</font>'
If you want this to be your full email address.
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