I experienced the same issue with my wireless connection, using Win XP Pro on both machines.

I found that the wireless management software installed with my wireless device was causing the issue. By disabling the installed wireless manger and enabling Windows integrated wireless manager, the issue resolved.

1. Click the 'Start' menu >> 'Network Connections'
2. Right-click on your 'Wireless Network Connection' and select 'Properties' from the menu.
3. Select the 'Wireless Networks' tab.
4. Add a checkmark to the checkbox "Use Windows to configure my wireless network settings" and select 'Ok'

You will need to reconnect to your wireless router using Windows wireless connection manager.

Hope this helps!

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