Email only has text and not html

Hi,
Ok I am a little confused here... have not touched anything (that I know of).. I have 1.3.7 and when I send a email newsletter or product update, it always has my logo at the top and it comes out in HTML format... well this time I sent it to me and it only has text and no logo and no highlighted words etc...
Also when I press enter in the letter and it gives me a blank line... it shows up with no lines or gaps int he preview...??

I have put in a dummy customer login and I got the welcome email and it shows it in HTML and has the logo ect but not when I send a Newsletter/Product information email...

Any ideas ??

Thanks
Dave
https://www.timeoutmassage.com.au/zen

Just thought I would add something... the email I get does not have the image X (as in its looking for the graphic)... its just a plain and simple text email... When I send the email to ADMIN as a test it shows it in text format only... I have selected ADMIN show in HTML in the email setup as well...

I have no idea...

In your Zen Cart Admin you will need to go to:

Configuration>E-Mail Options
and make sure that you fill this area out.

Real important to put the true value on "Use MIME HTML when Sending Emails".