Ada wrote

According to my experience, you should email to support@tp-link.com instead of supportengineer.

You still get this email error message. I have gotten this message and TP-Link was still able to respond

Catherine Duan replied:

The guest network, can be assigned a different SSID and password. And you can setup the guest network cannot access/communicate with the main LAN network.
In that case, even though they share one DHCP settings, but the clients in guest network cannot access the main network, that is to say, cannot share the file within main network.

Guest network share one MAC filtering settings with main wireless network.

This is the designed feature of guest network of our routers. Sorry that it cannot meet your requirement, but our R&D department will evaluate your suggestions.
If possible, we will add it to our our routers in future.

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I just ordered a WDR3500 for my guest network that I'll plug in to my WDR3600 that I only use in wired mode. When it arrives, I'll have to play with it and see if their guest network isolation really works. In the mean time, I've had no problems implementing guest networks by cascading secondary routers off of my main router where the DHCP servers all serve up the same range of IPs (192.168.1.128 to 192.168.1.254). This will be the third secondary router and should give me good Wifi coverage for the back of the house.

Hmh, to what email you sent your query?

I didn't sent an email. I just used the support page on the website -- the one that sent me the error message.

Any news about this problem?

Hap Hapablap wrote

Any news about this problem?

So you still haven't contacted TP-LINK technical support?
You should contact them directly and feed it back as a suggestion like fepcoder. Not so many people have such needs.

For the original request of separating the MAC address filtering between the guest network and the non-guest network, I was told that it works the way it's designed. They seemed to ignore that it's simply designed wrong.

As a follow-up post, I determined that the SSID transmission is inconsistent between the two frequency bands. So, with one, if I disable the non-guest SSID, it disables the guest SSID as well, but not for the other band. They accepted that as a firmware bug.

I understand the different, but am unsatisfied. A bug, design or coding, is a bug and should be fixed.

If more users request for modification on this "design problem", maybe it will be improvd in future. :)

This is the designed feature of guest network of our routers. Sorry that it cannot meet your requirement, but our R&D department will evaluate your suggestions.

Guest network working very good on OpenWRT/Gargoyle. I have configured in my job and I'm very glad - http://wiki.openwrt.org/doc/recipes/guest-wlan