if possible connect RE to dhcp server

You can set a solid wireless channel on your root AP.
And if necessary, upgrade the TL-WA830RE...

Kane explain how to upgrade firmware TL-WA830RE Ver.1 & Ver.2 only have first firmware/factory firmware quaresma07 its only able to reload firmware

my AP has a solid wireless channel same as on RE, both is 11,about firmware it can be tried, thnx

danymarc wrote

Kane explain how to upgrade firmware TL-WA830RE Ver.1 & Ver.2 only have first firmware/factory firmware quaresma07 its only able to reload firmware

yes i think my firmware is the latest one "TL-WA830RE_v1_111108"

quaresma07 it would be nice if you elaborated your threads by posting info. some of the devices have issues with security sometimes WEP others WPA you have not posted what security you are extending, how far are you from Airties (war-141), about connect to RE, what are you connecting, SmarPhone, Lap etc. as you can see this is not a guessing game, to get help post info.
about the channel, forget about it, when you use RE mode, this is not and issue for you now.
Start by factory default your RE with pin, http://www.tp-link.com/en/article/?faqid=426 then reload firmware and set it again, if you have same problems after this, enable DHCP to RE just remember you have to be in a dif subnet to avoid IP conflicts like 192.168. 2.0