Problem upgrading from v3.0.12 to v3.2.5

Hello, I upgraded an install from v3.0.12 to v3.2.5 and had an issue with the html versions of newsletters sent. Unfortunately I am unable to provide anything really substantial other than to state that emails received on windows 7, windows vista in thunderbird and outlook were malformed with images missing and spaces introduced so that it was virtually unreadable.

I checked the html I wrote in an editor and it was fine. No issues.

I then rolled back to v3.0.12 and sent the email without a problem.

What can I do to help resolve the problem?

@opalepatrick see this earlier topic for a likely solution BUG / Hotmail / phplist 3.2.3