Windows 7: connected to wifi network, but can't connect to internet..???

i've had a wifi network set up at my house for several months now, and no problems. if i couldn't connect...i always just unplugged the router for 10 seconds, and was able to connect. well, suddenly today...i can't connect to the internet, but my wifi network appears to be fine. it's says i have excellent signal strengh and that i'm connected..but i can't connect to the internet. when i go to the program that came with the router..and hit "repair"..it says that i AM connected to the network, but that my internet connection is broken...??? what UP with that??? i don't get it. can someone please advise on what to do? i tried using another device to see if i could connect with internet, my ipod touch....and it also said that i was connected to the wifi network...yet it could not connect with the internet. it never had a popup that said anything..it acted like it was trying to connect..but just never did. i'm puzzled.

during the day while i was at work, my roommate was going to use the laptop, when she couldn't connect, she did the unplug for 10 sec. thing...whent that didn't work, she unplugged the two cables from the back of the router, and plugged them back in. is it possible that she plugged them into the wrong place? would that be the problem? i am not at home right now, so i can't check...but will try to fix this when i get home tomorrow. not sure what i need to do!!

signed....frustrated!!

Willing to bet you are using a third party firewall / antivirus application.
Which one is it?

well...i'm not computer savvy...so this answer will probably seem lame, since i'm not quite sure exactly what u mean! lol! but i recently had a virus...one called "system tool"...it was nasty! since then, i have installed avast...i was supposed to have had protection thru comcast, my provider...but could not find anything! i had used avast in the past, and had no problems. also have some mcafee stuff, i think. is this what u mean?? i'm only using freebie stuff right now...like i said, i was supposed to have some of extra protection thru my paid service, but apparently i do not. what should i do?

ah, okay the virus wasn't cleaned properly.
this is going to be a bit involved.
First I'm afraid I'm going to have to ask you to remove avast! that can be done under programs and features in the control panel.

Then we are going to boot safe mode with networking.
Safe Mode

Once you are in there download and install malwarebytes antimalware (the free version is fine for this)
Malwarebytes
Install it and allow it to update.
If you can't get through in safe mode with networking just post back I'll come up with a alternative.

Run a full scan - (this will take quite some time, so go grab a soda or watch a little tv)
Once it's done scanning allow it to remove whatever it has found.

Reboot to normal windows mode.
Test the connection and report back.

Sorry to be so involved but without being there it's the only way I know exactly where we stand...

wow, thx i appreciate it! i'm wondering why it worked after the virus at all then..?? it's been fine...up until today. once i "removed" the virus...i saw no signs of it. at least..i thought not. sooo....it sounds like ur pretty sure that's what it is...so that's what i will try. not home now, so it will be tomorrow. i will report back and let u know!

Well it could possibly be an issue with avast! as well, which is why I put removing it as the first step.
Doing this kind of thing over the internet is usually trial and error.
So I'm just removing all the unknowns I can right from the start.

oh yeah, would like to add...that i did use reboot in safe mode, and did the system recovery thing....so...that wasn't enough? just trying to fill in details i left out before that might help with your "diagnosis"!!!

What's been affected is either a system service is being blocked by avast! (either the program got over zealous or incorrect user input was provided at some point)
Or a basic internet setting has been corrupted.

Before we go to any greater length, can you verify that this problem occurs in any browser beside internet explorer? ie. firefox, opera, safari?

well now, that is a good question, cos i was wondering that myself. i use google chrome. and i never tried it on any other browser, but thought about that when i left. but....when i tried to connect on the ipod touch...i just hit "facebook" icon...and it didn't work. it was trying, but never connected. so..that was..safari? i don't know. i think i have google set as my search engine on ipod touch..i have no idea if this is even relevant or not. sorry. i'm just offering up what i can!

okay, you lost me, the ipod touch is connected to the same router as the computer in question, or is it somehow bridged through the computer's connection?

It's starting to sound like a router issue if it's affecting more than one device.