i think this code solve your problem.
<div class="email_pot">
<a href="mailto:abc@abc.com?subject=my subject&body=see attachment&attachment="+"/my_location_virtual_path/myfile.lis"></a>
</div>
Whether you can put a file attached to an e-mail depends on the mailer. (but many mailers can't add attachement file from maito:protocol)
I think I was able to put the attachments in some versions of Outlook, perhaps.
So, what's your question? I will assume that you are getting some error when you tried to send the email. I have answered a very similar question before:
According to RFC 2368 you can't add an attachment to a message with the mailto: URL scheme due security reasons:
The user agent interpreting a mailto URL SHOULD choose not to create a message if any of the headers are considered dangerous (...) Only the Subject, Keywords, and Body headers are believed to be both safe and useful.