I think I am IP banned from certain sites, any help appreciated

[kevin1212]

Whenever I try to access certain sites I get an error saying my browser cant' find the site.  Also MS update has failed for awhile now (error 643).

Today I tried using a free webpage based IP proxy.  I was able to access the websites that I normally can't (listed below) as well as initiate a download from one of them.

I access the internet through a ADSL connection.

My thoughts are that I am IP banned for some reason from these sites. 

I run Avast antivirus and have done so for nearly the entire life of this computer (aprox. 6 years.)

Sites I can't acess:

Microsoft downloads (includes windows update)
OCtranspo (bus service)
overclock.net (gpu/cpu overclock site)

Google chrome error when trying to access: Oops! Google Chrome could not find www.octranspo1.com

I"m fairly certain my computer has adware.  I have had the same copy of windows for 5 years now and I am planning on buying win 7 to do a clean install.   I get an error if I try to reinstall windows using the manufacture boot restore (no win vista DVD was supplied).

I've had a look through the ADSL modem's firewall settings and windows firewall to see if I could find anything abnormal with no luck.  I am very inexperienced with firewalls and have little knowledge about them.  From my understanding they are meant to block outgoing connections and not incoming.

My questions:

IF I am IP banned, is there a process to get my IP unbanned?
Will reinstall windows 7 do anything to make these sites work?
Can I change my IP?
Can my firewall block me from accessing certain sites?
If someone used my computer to attack these sites, will a clean install of win7 remove whatever malware may be on my computer to enable such an attack?

[Geek-9pm]

You could contact your internet provider and ask them.

Here are some things you can try.
If one of our neighbors also has the same service, he may also have the same IP address. Ask him if he can get to those sites and what is his network address on the internet.
http://whatismyipaddress.com/
Above is one of many sites that give you IP as seen over the internet.

Another option. There are very low cost dial up services that you can buy a few hours very cheap. Use one of these with dial up modem. You will get a different IP address  from them.

You can turn off your firewall for a short while and see what happens.

Do a complete scan of your system. You might have some kind of thing that stops you from getting to some sites.

[kevin1212]

Well I can access the sites i'm normally blocked from using a proxy I would imagine that would give me the same results as using a dialup service to get a different IP.

I"ll look into trying to use a neighboors computer although I'm pretty sure IP addresses are assigned per account from ISP.  I think I'll get a friend to come over with a laptop though and try to access the sites through my ADSL router.

[Allan]

Have you tried a different browser?