Cannot access certain sites! HELP!

[tehk]

This has been a problem for a long time... For about a month, I've noticed that I couldn't access this certain site which I visited often (http://www.mysongbook.com), so I figured the server was down, or the site was under construction or something. But then, my friend went to that site from his computer, and he said it worked perfectly fine. On that same day, I tried going to that site on my computer, but it still didn't work (I tried with both Opera and Internet Explorer). One day I brought my computer to my friend's house, and hooked it up to his internet, and the site worked fine. When I brought it home, I noticed more sites stopped working for me http://www.good-tutorial.com and also http://www.spoono.com. Can anyone help me? Thanks for your time, and thanks for reading this long question.

[Melodi]

Hello!
Often when this happens it's a result of a virus or malware. You might try dumping your internet files to see if that helps. In a browser, go up to tools, down to internet options and then click delete files. That might help. Also try these tools to check for spyware.
Please let me know if it helps.
Adaware: (use option to search for updates)

http://download.com.com/3000-2144-10045910.html?part=69274&subj=dlpage&tag=button

Spybot 1.3:

http://download.com.com/3000-8022-10122137.html
For advanced cleaning

Trendmicro:

http://housecall.trendmicro.com/ choose ‘scan now it’s free’

[tehk]

I tried all of them, and it stills doesn't work. I'm pretty sure it's my internet and not my browsers, because when I brought my computer to my friends house, everything worked fine, but when I brought it home, the sites didn't work again. But then again, I have 2 computers in this house, and on the other computer, the sites work perfectly fine. Thanks for the help, I really appreciate it .