hoc can i sent the html newsletter

[Sworm]

Hi all,
how can i sent from the emails tool of vBulletin 3.68 a html massage that can be reading by all email clients?

Today i've test this option and i've write a html email with associate css file, and i've sent it to myself, but when i go for reading it with Ms outlook,
i can read the mail only in txt format and i don't see nobody images nobody links etc....the html is correct and css too.

How can i do for sent a html email that can be reading by all email clients?

Anybody can help me?

Thanx