Yeah that is really ODD!
I just sent your source to my local version of Outlook 2007/Vista and everything rendered correctly:
http://www.emailonacid.com/images/acidtest/disneyland.jpg
Then I re-ran the same source in our testing platform and I see the same white box that you did in Outlook 2007 but not in Outlook 2010:
Acid Test Result
(link will expire in 15 days)
I don’t think it’s a screen capture issue, it might be caused by a Windows update or version of Windows.
I also tried adding a DOCTYPE so that I could validate your code. The only potential issue that I see is on line 146. You are missing a close </span> and you need to remove the close </font>. But I really don’t think that’s what is causing this.
In looking at the interpretation from Outlook 2007, that line of text this is in the white box is not broken out:
<p class=MsoNormal align=center style='text-align:center;'><a
>&url=http://offers.disneylandparis.co.uk/flash-sales/index.xhtml?ecmp=y&cliczone=VISUEL1"
target="_blank"><span style='font-size:8.5pt;font-family:"Arial","sans-serif";color:white;border:none windowtext 1.0pt;padding:0in;text-decoration:none;'>Kids under 7 or 12 get </span><strong><span style='font-size:10.0pt;font-family:"Arial Black","sans-serif";color:white;border:none windowtext 1.0pt;padding:0in;text-decoration:none;'>FREE</span></strong><span
style='font-size:8.5pt;font-family:"Arial","sans-serif";color:white;border:none windowtext 1.0pt;padding:0in;text-decoration:none;'> hotel
& park tickets depending on your arrival date!</span></a></p>
I have never seen anything like this glitch before, I will run it by my dev team to see if they have any ideas.