BleepingComputer.com: My Laptop Will Not Connect To Any Networks!

This is strange. 2 weeks ago I was able to plug right into our work router to gain access to the network & the internet. Suddenly last week I can not connect to anything thru a CAT 5 network cable. I can use wireless devises to get online (I'm doing that currently) thankfully. I thought it was some type of firewall or security issue at work. When I got home I still could not connect thru the cable. I did the "tried & true" first step. I unplugged the modem-router & pc. I turned the modem back on, then router, then pc. Nothing changed. I checked my desktop & it was getting online just fine. I even ran the cable from the modem directly into the Laptop, no luck. Looking at the port I see the green light does come on, the yellow light comes on periodically but seems to go away. My laptop shows a window saying the Local area connection is now connected 100 Mbps. But when I go to open a browser I get error window saying "problem loading". I go to command & try "ping www.yahoo.com", it fails. I thought maybe it was a firewall thing. I set "Sygate" to "allow all". Still couldn't make it work. I'm at my wits end. Can anyone help me figure out this problem?
Thanks!

ping your router's IP address (usually 192.168.2.1, or perhaps 192.168.1.1)

A week ago or so, I couldn't connect to the internet either... Scan your system with Ad-aware or something and make sure its not a dialer program. It took me long enough to catch it....

I tried to ping the router using: 192.168.2.1 & 192.168.1.1 & 192.168.0.1 I got nothing. I ran 2 antivirus scans. I still got nothing. A different forum mentioned doing a ipconfig/all. I did that to my laptop which does not connect to the net & my old desktop which does connect without any problems. I hope none of this info creates a security risk for my system. If so ooops! I hope this info is helpful.
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Windows IP Configuration
Host Name.....................: its correct
Primary DNS Suffix............:
Node Type.....................: Unknown
IP Routing Enabled............: NO
WIN Proxy Enabled.............: Yes

Ethernet adadpter network bridge:
Conn-specific DNS suff........:
Description.....................: MAC bridge miniport
Physical address..............: B2-95-1E-F2-5D-70
Dhcp Enabled..................: YES
Auto config Enabled...........: YES
Auto Config IP Address.......: 169.254.212.177
Subnet Mask...................: 255.255.0.0
Default Gateway...............:

Ethernet adapter Local connection:

Conn-specific DNS suffix.....:
Description....................: Realtek RTL8139/810x family fast ethernet NIC
Physical address..............: 00-02-1E-3F-35-7D-D5
Dhcp Enabled..................: NO
IP Address....................: 192.168.1.99
Subnet Mask...................: 255.255.0.0
Default Gateway...............:
===========================================
I did the same with my desktop which is connecting fine. Here are the results:
============================================
Windows 2000 IP Configuration
Host Name.....................: its correct
Primary DNS Suffix............:
Node Type.....................: Broadcast
IP Routing Enabled............: NO
WIN Proxy Enabled.............: NO
DNS Suffix Search List........: nyc.rr.com

Ethernet adapter Local connection:

Conn-specific DNS suffix.....: nyc.rr.com
Description....................: D-Link DFE-530TX+ PCI Adapter
Physical address..............: 00-50-BA-5B-E5-EE
Dhcp Enabled..................: YES
Auto Config Enabled.........: YES
IP Address....................: 192.168.15.100
Subnet Mask...................: 255.255.0.0
Default Gateway...............: 192.168.15.1
DHCP Server....................: 192.168.15.1
DNS Server.....................: 24.29.103.10
24.29.103.11
Lease Obtained sept 18 2007
Lease expires sept 19 3007
====================================
I don't know what any of that means but I hope it will shed some light on why my Desktop is connection to the internet but my Laptop is not, even thought they are using the same router.
Thanks!
===========================================

Try copying the MAC address (physical address ) to the laptop. Most Broadband cable providers allow you to network your own home using a router but they only issue one Mac address. To find out your MAC address, Go to the run menu and type command, once your in the DOS window type Ipconfig /all next to the line physical address is the MAC address. Write this down, this is the alphanumeric number you need. Go to the laptop
This is depending on the type of Network Interface Card (NIC) you have. If you have a card that doesn’t support Clone MAC address, then you have to go to second method.

• Go to Start->Settings->Control Panel and double click on Network and Dial-up Connections.
  
• Right click on the NIC you want to change the MAC address and click on properties.
  
• Under “General” tab, click on the “Configure” button
  
• Click on “Advanced” tab
  
• Under “Property section”, you should see an item called “Network Address” or "Locally Administered Address", click on it.
  
• On the right side, under “Value”, type in the New MAC address you want to assign to your NIC. Usually this value is entered without the “-“ between the MAC address numbers.
  
• Goto command prompt and type in “ipconfig /all” or “net config rdr” to verify the changes. If the changes are not materialized, then use the second method.
  
• If successful, reboot your systems.

Follow this Link for steps 2-3. If the previous step doesn't work


Ethernet adapter Local connection:

Conn-specific DNS suffix.....: nyc.rr.com
Description....................: D-Link DFE-530TX+ PCI Adapter
Physical address..............: 00-50-BA-5B-E5-EE <<<------ it will look like that number
Dhcp Enabled..................: YES
Auto Config Enabled.........: YES
IP Address....................: 192.168.15.100
Subnet Mask...................: 255.255.0.0
Default Gateway...............: 192.168.15.1
DHCP Server....................: 192.168.15.1
DNS Server.....................: 24.29.103.10
24.29.103.11
Lease Obtained sept 18 2007
Lease expires sept 19 3007

This post has been edited by Sneakycyber: 18 September 2007 - 04:21 PM

******************THIS FIXED IT!!**********************************
I DON'T KNOW WHAT ANY OF THIS MEANS BUT I DID IT AND PRESTO I WAS BACK ONLINE!!
-I wanted to put this on the forum for anyone else who was having a hard time like me.
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TCP/IP stack repair options for use with Windows XP with SP2.

1) Connect the laptop cable to the router, then do this:
2) Start, Run, CMD to open a command prompt.
3) "Reset WINSOCK entries to installation defaults"type) netsh winsock reset catalog
4) "Reset TCP/IP stack to installation defaults": (type) netsh int ip reset reset.log

5) Reboot the machine.

Thanks for the solution