I have just coded an email design, tested it in Litmus & found out the following errors:

Outlook.com: There was no background image for the newsletter & some of the headings (h4) font color is totally different. Although the same color is OK for the links. outlook 2003-2011 works fine.

Hotmail: Similar is the case for hotmail as it also doesn't show up the background for the newsletter.

Here are the litmus results.

https://tahir.litmus.com/tests/9401666/versions/2/screenshots

Thanks.