Intereresting, this is the second time I've tried to go to a page using a link posted in a forum thread in which I've gotten a strange error message. Last time it was a malware message, this time it's this:
This "is" a work computer, but that is not the warning we get when we go to a blocked website. That button that they say to click on kind has me going "hmmmmm............"
Sounds like you have a malware program running. They typically popup fake warnings like that. I would run a scan with spybot search and destroy and see if it detects anything.