I have a remote office with 7 workstations/laptop computers, all are running Windows XP Pro except for 2 new Toshiba Laptops. Both Toshiba laptops are running Windows 7 (one 32-bit the other 64-bit). These are new laptops (purchased within the past couple months). Both laptops are having dropped network connection several times a day. This is a wired network with a single Windows 2008 R2 64-bit server and one nework switch. All the XP machines have no network drops, only these two new laptops running Windows 7. The only way the laptops restore their network access is by disabling/enabling the network card or rebooting the laptop. Event Viewer on laptops and on the server shed offer no help in diagnosing the problem. I have disabled IPv6 on the both the server and both laptops, rebooted all the machines but that has not helped. I "turned-off" the power management on all three network cards, rebooted all machines but that has not helped. Can someone shed some light on what might be causing this problem?

Are the windows clients using 802.1X authentication ? If yes then apply this hotfix http://support.microsoft.com/kb 980295

Yes, they are using 802.1x authentication. Thank you for the link, I will give it a try and post the outcome.

I think applying this patch would resolve the issue and if that doesn't woork apply this too Windows 7 may connect to a guest network instead of a corporate network http://support.microsoft.com/kb/2481614

That particular fix looks like it is just for wireless networks, this is a wired network.

It is even valid for wired 801.x, But first apply the First patch and see.

Ok, thanks for all your help. I hope the first fix works because these two users are having fits over this.

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