What's the model of your access points? If your access points are ceiling AP, you can enable the Load Balance feature in the page 58 on http://www.tplink.com/res/down/doc/EAP_Controller_Software_V2_UG.PDF .

Excellent that's just the info I needed Thanks

NIge

We've just installed this in our office. One upstairs and one downstairs- Easy to set up.

We have an issue where periodically the users get disconnected from the internet. They are still connected to the wireless though. We have 2 AP's and they are set up so it appears as one SSID.

When we do a troubleshoot on windows it says it can;t find the default gateway. If we disconnect and reconnect it usually works. But also it might just fix itself. It seems that if we disconnect one of them it works fine. So I think its something to do with clients switching from one AP to the other...

Any Ideas?

Have you set the RSSI function before, refer the UG http://www.tp-link.com/res/down/doc/EAP_Controller_Software_V2_UG.PDF page58 to have a check.
And i doubt that when you use the same SSID for two EAPs, it could be the weak wifi signal that you connect. You could configure the different wifi name for each EAP, when you are upstairs, connect the one which installed upstairs. when you are downstairs, connect the one which installed downstairs. Also check whether it works.

We have the same issue as nigelg with most intel based wifi cards. Depending on the model an older driver might help, but newer cards you are SOL.

Upgrade the firmware from www.tp-link.com too.