RATTER, I've just tried your website with both browsers and wonder if the problem links are the same as Ethel found.
Products - Search - Links. These three don't work with IE7, but all do with Firefox, plus the same Error On Page as I had. The next update should hopefully fix these bugs.
Ethel and Cetti, many thanks for checking that out for me, I hope IE7 gets this sorted, this could be costing me money if people don't bother to try another browser!!
Ratter: no, all these issues won't be fixed until IE8. Wait another few years ;)
This is why Microsoft can be such a crap company.
wookette:
Sounds like your firewall is blocking access. Do you use norton as your firewall, or something else like zonealarm? Try disabling it temporarily, and then trying IE7 with your sites you can't gain access to.