My mom has a Dell Inspiron 1564.

She's running windows 7, and connected through a home wireless connection that runs three other computers (1 laptop, two desktops) not including a cell phone, ps3, and wii all that connect and browse the internet currently.

All of a sudden, her laptop wont connect to the internet.  All other devices connected to her motorola router work fine.

 The way you turn on/off your wireless connectivity is through FN and F2 together.  So i figured it was that, tried it with no luck.  I've tried troubleshooting through NETWORK, and even through yahoo messenger (Which gives the 'youre firewall may be blocking, your capability is tuned off, dns has an issue, etc results).  I've trned her firewall completely off to try with no luck, replaced and tried toggling wireless a few times with no luck.

The only thing i can think of is she must have a virus (I think BACK to the nightmarish "Antivirus 2009/2010").  I remember installing/having her install Ccleaner a while ago on her laptop, i dont see it anywhere now in a search or otherwise.  I do see that now she has McAfee and she's never used it/wanted it (etc) so im wondering if its a mcafee virus?

Nothing else seems to be an issue.  Her files are all still there, no weird sounds/colors/etc.  I hope ive been detailed enough, and im really hoping someone can help!

Thank you for your time.Have you tried connecting with a wired connection to the router to see if the internet/network capability works at all?
Also, I would check some of the network settings. Start Menu -> Control Panel -> View Network Status and Tasks (in the very top section). Then in the left-hand pane, click on 'Change Adapter Settings' Right-click on 'Wireless Network Connection'. If there is an 'Enable' option, try clicking it, and then try connecting again. If not, go down to 'Properties', and scroll to the 'Internet Protocol Version 4 (TCP/IPv4)', click on it (but leave the check mark there) and click the 'Properties' button. Check that it's set for 'Obtain an IP Address Automatically'.hi there
First of all, try to get connection through the ethernet cable connected directly to the laptop and check if you can surf,
If u already diable and enable the wireless connection, and nothing HAPPEN,
try to do this, click on start,on the search programs and files, type cmd and it will appear a black screen, on the blinking little bar type ipconfig, check on IP ADDRESS OR IPV4 ADDRESS ,the first 3 NUMBERS that must appear are 192 if u have something different like 169, there is a nics card problemIs the wirless icon illuminated on the deck of the computer? Looks like this  ((0)).
On some laptops, there is a pushbutton to turn off wireless networks for secure offline work.Allot of routers have a place to allow access only if the MAC address is listed (same with some modems).  If this was TURNED on and the computer is not listed.

Have you tried (like other suggested) connecting directly to the modem and router via cable?  Check the IP Address to make sure that it is not being used by another system.