Can't access certain sites

There are certain web sites that I just can't get to. Some sites I could reach, but stopped working later. Some sites just never worked for me. But there's no problem with the computer & internet. All other sites work. I've contacted my internet provider, reset router, changed router settings, played around dns, hosts file etc. but none worked... I know I'm not blocked.

There's one site that I could access with no problem a week ago, but now, it only allows me to view like 3 pages, then it just stops loading and gives me a "cannot find server" page, then I have to wait a few minutes. After that, it allows me to view 3 pages again... It's not spyware or firewall related. I've also tried format & reinstall everything, still doesn't work.

This has been a problem for at least 1~2 years, & I still don't know what the answer is. And it's really getting annoying. Certain PC on the same network work, some don't. Some worked before, but not anymore. I also tried accessing those sites at work, same problem... Strange...

Can anyone please help me with this??

if u can't access them at work on another system/ip setup entirely then it's the site
email the site admins if u can find a email for them and tell them the problem then let them (hopefully) work it out
sounds like from what u posted that it's a problem on the sites not your end so nothing u can do really