I had pasting problem in Office 2010. Made search in Google, there was hard to find an answer also, but at last I figured it out.
In the first forum that I found I wasn't able to register. This is second and I post a solution here.
In Office 2010: New E-Mail -- File -- Options -- Mail -- Editor Options (Compose Message) -- Advanced -- Cut, copy, and paste - Pasting from other programs -- Keep Text Only -- OK
Regards,
Koit Lahesoo