Safari Won't Open Certain Websites

Hi-

My Uncle just purchased a new Macbook Pro with Snow Leopard and he is having trouble accessing certain sites such as AOL.com and Firefox.com but has no problem accessing other sites like Apple or Google from Safari.

I tried to troubleshooting the issue by resetting Safari and by deleting the com.apple.safari.plist preference file in his home directory but he still has the problem.

I'm not sure if it is related, but I had to have him change the port from 5190 to 443 in iChat in order to connect to his AIM account so I could screen-share with him.

Also, he uses AOL mail and I was able to get it set up in Apple Mail but it is very sluggish to download.

He is using either Cisco or Linksys router and range extender and he said that his Windows computers have no problems connecting to any sites.

Can anyone give me any tips on how to troubleshoot this further?

Thanks in advance

 

I'll have him try restarting, and check out the DNS setting, router firewall settings, and make sure no ports are blocked and report back.

I was just wondering if I was missing something obvious as I've never seen an issue where only certain sites won't load.

 

I just wanted to update this post in case someone else had this problem. My uncle's router was a WGR614v7 Netgear Router and I was able to resolve this issue by manually entering the DNS numbers in the router settings. This seems to be a bug in the way this model of router or OS X handles DNS relay because setting the router to automatically retrieve the DNS information from the ISP would not work.