Hi jpat_mcm,
Welcome to Microsoft Answers!
What message do you get when you try to go online using Internet Explorer or Mozilla Firefox?
Do you remember any changes made to the computer since a week?
Which among the two is your default web browser?
Did you try resetting the router or modem?
Did you check whether you're able to go online in Safe mode with networking?
Based on the information that you've posted and on the research done, I would suggest you to try the following steps in the link below.
Steps to boot the computer in safe mode with networking. a. Restart the computer and start tapping the function key F8.
b. On the Windows Advanced boot options, select Safe Mode with Networking and hit Enter.
c. Once you’re at the desktop, try to browse some websites.
http://support.microsoft.com/kb/956196
I would also suggest you to go through the following links
http://support.microsoft.com/kb/299357
http://windows.microsoft.com/en-US/windows-vista/Troubleshoot-network-connection-problems http://windowshelp.microsoft.com/Windows/en-US/Help/fc58605e-a2be-470c-95b3-6808a76347991033.mspx Hope the information is helpful.
Regards,
Mouneshwar R - Microsoft Support
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