Windows 7: Laptop can't discover/connect to wireless networks.

I have been having this problem for 2 days now. My computer was working fine, and I went to go do something, so I shut my laptops lid to put it to sleep. I came back about 5-10 minutes later, and it had a red cross on the network button, at the bottom right of my desktop. I tried turning the Wi-Fi on/off with F2 + Fn, but that didn't work. I have checked in device manager, and everything seems to be working. My wifi card is an Intel(R) WiFi Link 5300 AGN.

Currently running this on a Dell Studio 1557, with Windows 7 Home Premium 64bit. I've had this laptop for almost 3 years now, and it has never been a an issue. I've tried restoring my laptop to a couple of days ago, but that has given me no results. I tried running the computer in safe mode with networking enabled. I enabled my wifi with the fn + f2, and I saw my wifi network. However, while it was connecting, the connection was lost again, and I'm yet to see it. After disabling and then enabling the driver, it would show the network for about 20 seconds, then it would be missing. Now, I can't even see it at all. All my other computers/devices can see my network, and it can still connect with it's Ethernet port. This problem is really starting to be a pain, since my laptop is pretty useless if it can't have portable internet. :P

Background Info:
Model: Dell Studio 1557
OS: Windows 7 Home Premium 64bit
WiFi Card: Intel (R)WiFi Link 5300 AGN
Antivirus: McAfee Total Protection 2011

IP Config results



Windows IP Configuration

Host Name . . . . . . . . . . . . : PC
Primary Dns Suffix . . . . . . . :
Node Type . . . . . . . . . . . . : Hybrid
IP Routing Enabled. . . . . . . . : No
WINS Proxy Enabled. . . . . . . . : No
DNS Suffix Search List. . . . . . : BigPond

Wireless LAN adapter Wireless Network Connection:

Media State . . . . . . . . . . . : Media disconnected
Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : Intel(R) WiFi Link 5300 AGN
Physical Address. . . . . . . . . : 00-00-00-00-00-00
DHCP Enabled. . . . . . . . . . . : Yes
Autoconfiguration Enabled . . . . : Yes

Ethernet adapter Local Area Connection:

Connection-specific DNS Suffix . : BigPond
Description . . . . . . . . . . . : Realtek PCIe GBE Family Controller
Physical Address. . . . . . . . . : 00-26-B9-10-F1-8C
DHCP Enabled. . . . . . . . . . . : Yes
Autoconfiguration Enabled . . . . : Yes
IPv4 Address. . . . . . . . . . . : 10.0.0.87(Preferred)
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Lease Obtained. . . . . . . . . . : Thursday, 6 September 2012 5:04:04 PM
Lease Expires . . . . . . . . . . : Friday, 7 September 2012 6:09:09 PM
Default Gateway . . . . . . . . . : 10.0.0.138
DHCP Server . . . . . . . . . . . : 10.0.0.138
DNS Servers . . . . . . . . . . . : 10.0.0.138
NetBIOS over Tcpip. . . . . . . . : Enabled

Hi,

I would first suggest you to create a new User Account and check if the issue persists in a new User Account or not? To create a new User Account in Windows 7, you can refer to the URL mentioned: http://windows.microsoft.com/en-IN/windows7/Create-a-user-account

If the issue still persists then try reinstalling the Wireless Driver of your studio laptop by clicking on the below mentioned URL:
http://www.dell.com/support/drivers/us/en/04/Product/studio-1557

You can even run the Troubleshooter, for that Right-click the network icon or in the notification area of your taskbar (Bottom Right hand corner), and then click “Troubleshoot problems” and follow the instructions.

You can even refer to the Microsoft Article ID: 956196 on the URL mentioned below which can suggest some more troubleshooting steps in case the Internet is not working:
http://support.microsoft.com/kb/956196

Please reply if you have any further questions.

No luck. My Wi-Fi still isn't working, even after trying all those things.

You aren't picking up anything from the router for the wireless connection according to the ipconfig.

You will want to perform a hard reset of the router then go back into the routers settings and redo the wireless settings, same SSID, same password, security and encryption. Routers lose the wireless side with the wired connections still working all the time.

Other computers can see the network. It's just my computer having the problem.

I just noticed that you are McAfee installed on this system....

Maybe you need to read about the McAfee update problem which has been causing connection problems. I believe this is the source of your problems.

McAfee - Resolving the recent update issues with McAfee Consumer Products

I uninstalled McAfee, and my wifi worked for a little while. But then it stops working again, and I have to run the troubleshooter again before it works. I'll have to see how it goes from here.

Just uninstalling McAfee may not work, there are other work fixes listed in the link that should help fix the problem that McAfee created.