Hi Snhuntley,
a) What changes were made to the system between the time everything last worked and when you noticed the problem?
I would suggest you to try the following steps:
Step 1: Disable the security software and check, follow the steps mentioned below
http://windows.microsoft.com/en-US/windows-vista/Disable-antivirus-software
Note: Enable the security software back once everything is done.
Step 2: Disable the DHCP Broadcast Flag:
Important This section, method, or task contains steps that tell you how to modify the registry. However, serious problems might occur if you modify the registry incorrectly. Therefore, make sure that you follow these steps carefully. For added protection, back up the registry before you modify it. Then, you can restore the registry if a problem occurs. For more information about how to back up and restore the registry, click the following article number to view the article in the Microsoft Knowledge Base:
How to back up and restore the registry in Windowshttp://support.microsoft.com/kb/322756/
Follow the steps mentioned in the link below:
Windows Vista cannot obtain an IP address from certain routers or from certain non-Microsoft DHCP servers
http://support.microsoft.com/default.aspx/kb/928233/en-us
If the issue still persists,
Step 3: Reset the TCP/IP stack: go to this article and either click on "Fix it for me" or follow the instructions to fix it yourself:
Reset Internet Protocol (TCP/IP)
http://support.microsoft.com/kb/299357
Step 4: Update the wireless network adapter driver:
You must be logged on as an administrator to perform these steps.
1. Open Device Manager by clicking the Start button, clicking Control Panel, clicking System and Maintenance, and then clicking Device Manager.
If you are prompted for an administrator password or confirmation, type the password or provide confirmation.
2. In Device Manager, locate the network adapter and then double-click the device name.
3. Click the Driver tab, and then click update Driver and follow the instructions.
Check the link to manually re-install the drivers
Update a driver for hardware that isn't working properly
Alternatively, download and install the latest drivers from the manufacturer’s website.
For more information, see the link below:
Troubleshooting Windows Vista 802.11 Wireless Connections
http://technet.microsoft.com/en-us/library/cc766215(WS.10).aspx
Thanks and Regards:
Ajay K
Microsoft Answers Support Engineer
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