Can connect to wireless network but not internet

I'll get to the Realtek download and uninstall COMODO tomorrow. My work load says bye for now and tomorrow is another day. Thanks for your help and I'll be back.

I uninstalled COMODO and followed your instr. I also updated drivers. Wireless is on. There is no change. Still cannot connect to internet.

You may need to hard reset your wireless router or else force the router to "reset" some parameters in the Admin GUI. Don't know why, but we sometimes have this problem with ours as well (a Netgear). I have to enter the admin GUI of the router (in my case RouterLogin.net - typically http://192.168.1.1 for ISP modems) and then tinker around in there and it will start letting me access the net again after a few things are refreshed. When it happens to me, it also says I'm connected but it still returns 404 errors on pages.

Another thing that I personally know can cause this is if the ISP's servers are being messed with, or the computer didn't get the new lease for the DNS. This is more common than the previous, and there's NOTHING you can do about it until the ISP resends that certificate/credential/lease to your modem.

This is a combo reply and additional info to both 2xg & EvilOzzmess.

As mentioned earlier I uninstalled COMODO, but I do have it installed on the Vista machine and (it's still there) have had it since purchase and it does not effect it. I still connect.

Re: Mac filtering and controls and settings and my personal access to the router: I access my neighbor's router (from my place of business) with the password given me. I still have access with Vista so the password is valid. I have no control over what he does but I know the password works. I also do not try to log in both machines at the same time to avoid conflict. I will disconnect either as necessary to experiment.

Re: other connections: I have a combination wireless & wired network at home that we have as many as 6 pc's connected at one time. I can connect there with no problem. However I have not tried another unsecured network. I have a source to do that but would have to set up guest access on Cisco.

I'll set up a guest account on another wireless router that I do have access to and try to connect there. It'll be a day or 2 though before I have a chance.

I connect fine at home with wireless but it's not a guest account. I'll reply again once I've tried another location as a guest. Thanks

I recently had a similar issue that turned out to be a DNS issue. I could ping my router but not sites (google.com) I could however ping 4.2.2.2

I typically got resolution by:
Start->run-> "cmd"

ipconfig/flushdns

I finally got a chance to try another location totally separate from my home or business. The business location on a shared connection as a guest is still a problem. At the new location I was able to connect as the home user and also as a guest user on an account I created with no problem.

When connecting at the new location my laptop wireless indicator still says no internet access once I've connected to the router. However, if I open a browser I get the Cisco Guest Password window. The password works fine and I'm in. Doing the same procedure at the trouble location I can remember the Vista machine doing the same. When I opened the browser the password window appeared. With the Windows 7 machine, when I open the browser, I get a window that says The connection was reset. Regardless of what I've tried the password window never shows. What would be the difference between the machines that the one will not allow the browser to continue with the guest password window?

Either way, I can connect elsewhere but not where I want to.

I know this is an old post, perhaps the following could help someone to connect using dhcp.
At one time dhcp worked on the Toshiba when one day "poof!" stopped working.

I did quite a few things on a Toshiba L755 laptop trying to restore automatic dhcp connections.
installed drivers, deleted drivers, reset tcp/ip using netsh, changed registry using microsoft fixits, changed registry manually, ipconfig/flushdns, removed anti-virus, checked for malware, rootkits and other unfriendlies, Unchecked ipv6 and misc ipv6 settings per techs suggestions. The only way I could connect was to manually type in network ip info for the wireless nic.

The list continues. But that is not why I'm posting.

I had almost given up and was resigned to the strange thought that even when all my other computers did not have any problems connecting to my wireless "n" router, the Toshiba L755 could not obtain a dhcp lease. Until I came across a website with instructions on clearing ipv6 "neighbors" and "destinationcache".

I was using ipv4 and doing the above makes no sense, At least to me. Well, I had nothing to use so I followed the instructions to clear and remove.

Opened up a cmd shell and typed the following:

first command was
netsh interface ipv6 show neighbors

next was:
netsh interface ipv6 delete neighbors

second command was:
netsh interface ipv6 show destinationcache

next was:
netsh interface ipv6 delete destinationcache

I removed the static ip I had set in the wireless nic and reconnected with a big sigh. Didn't expect anything since it was ipv6 and I'm using ipv4.

To my surprise, it connected for the first time since losing the ability to obtain a dhcp lease.
4 reboots later it was still working.

So, did doing the above fix it? I don't know. My dogs like typing on the computer and perhaps, just perhaps they entered in some registry settings which made it work, when I wasn't looking.

Or it's all just a coincidence. Either way, if you were just as frustrated as me, it can't hurt to try. If it doesn't work, well, on to the next possible solution.