I have had this request from a few customers over the years and it’s converting and using the description of an email is trickier than you initially think it will be. This is a question which often appears on the CRM forum quite regularly as well.
The reason for this is although the email looks like plain text when you see it in CRM, when you get the value of the Email entity description (main body of the email) you will also get all the HTML tags.
The scenario I had when I was doing this was the customer wanted to convert an email into a case and get the values from description.
So to do this I had to strip out the HTML tags and a few other things, which I did using a plugin
if you have to do this here a couple
This blog post is excellent
A sample plugin
Recently I saw Steve Green had created a CRM Video going through the process and I thought I would promote the video on the blog because he also has a link to the code here https://dl.dropboxusercontent.com/u/4041841/CRMDemo2014.zip
I would also recommend anyone who wants to learn CRM development to go through Steve’s other CRM videos, many of them are in CRM 2011 but the code would still work in CRM 2013.