This is my first time using Campaign Monitor, though I am familiar with sending out email campaigns.
I sent myself a test of the campaign, which worked great in Firefox.
When I tried to open the same email in Internet Explorer, none of the links worked.
(using IE 7)
We only tweak the URL's to go through our servers and then instantly redirect to yours, so not sure what's going on here. If the email worked fine in your email client, then it must be a problem with how it's been opened in IE I assume. Hope that helps.