Why won't my PC access certain sites anymore?

Did you get this resolved? It could be a number of things, such as the web site itself but if your still having the same trouble and you've checked your internet settings and any programs like parental control, then it's likely to be your isp. I hope it's fixed though. :)

Well my friend at the first look I think it is a problem with the Internet auction settings. Please check your security level. If it is set to maximum or even a high then there are a lot of sites which are not in the list of those security levels and so it may be blocking you from going to those that sites. And also I would suggest you to check the firewall settings of your antivirus it will have one because sometimes even the firewalls have been tweaked so that you do not access a few sites which are not in this safe list. These kinds of problems are faced a lot and I think these two things may solve the problem to the maximum.

Well as the one person stated it could be something with your ISP or something in your area causing it not to open correctly. I have had where no one in my area could access a site but in other areas of the country they could. The internet can be very strange. Something you may want to check though is if you have downloaded any new programs. I have had some mess it up where I couldn't access some sites. It shouldn't effect it but it has happened, for myself it was with realplayer. When I had that on my computer I couldn't visit any sites hosted on tripod (including my own sites at the time). Other then that I'm not sure what could be causing the problem. Hope that helps.

Have you tried with another browser? Tried with another PC at work or at school? It could be your ISP blocking the site if your home one cannot access it anymore...