pain in the "you know".. Thanks so much for this great tutorial. Say though, I'm having trouble getting your code to validate using the validator that you linked to. It reports that the xmlns attribute for the element html is missing. Also it doesn't like any of the attributes for the body tag like leftmargin, etc. So I wonder does this really need to validate, and I need to add the missing xmlns attribute and replace the body attributes with css style inline or just not worry about it? Any thoughts? Hello Chris, you make some really good points. I went back to my code that worked for all email clients including Outlook using the methods above and there were many elements the validator did not like, although I didn't get the error about the xmlns attribute. The answer is that validation is not necessary but you can use it to check for basic HTML errors like not closing open tags. I'm sorry to not be more sure about this but it's been a while since doing HTML emails as I now always use online WYSIWYG editors (which have their own issues but, at least, always get the emails looking the same!) I have re-written that section about validation to include your points and you may like to try this special email validator: http://premailer.dialect.ca/ Thanks, Rob! I suspect you are right that some of the things I mentioned which don't validate are not critical. At this point, I'm struggling with