IE7 (32 bit version), Vista Ultimate, SP1, x64 bit OS, UAC disabled (so protected mode in IE7 is disabled)
Did you try turning off the protected mode?
Yes, I have webmail.freeshell.org in the "trusted sites" zone and it says "protected mode off" when I go there.
I also tried turning off UAC, I still get only "internet explorer cannot display the webpage"
When I do "winver" I get Version 6.0 (Build 6000) Says 32-bit operating system. So that's different from yours. It's Vista Home Premium. I'm pretty sure I don't have SP1, that sounds like something you buy and I haven't bought any upgrades to Vista since I installed it April '7.
IE is version 7.0.6000.16609, cipher strength 256-bit
I've installed all the "important" and "recommended" updates I've gotten.
I know viruses can cause weird behavior, but having found this problem mentioned online on the atlassian.com website, not having any virus symptoms, and having scanned my whole computer with an antivirus program (and with windows defender) and nothing came up - if it were a virus, it's an eerily silent one ...
Do you think your operating system and version of IE7 is significantly different from mine? Maybe it's something that's been fixed in newer versions of Vista, it sounds like your version is newer.