We have 14 total APs running internal and a visitors networks. I have some guests that are trying to connect to the visitors network but in that area they can not get connected, If they do get connected it will go in and out but the internal is working fine. This has never been an issue before and the internal connects fine. Any thoughts as to why the internal would be working fine but the visitors would not let them connect. Nothing has changed with the setup.
Look at the Support Info file from the AP "in that area" where clients can't connect to the guest network well. You may have an interference issue, and might need to change channels to improve performance... but Support Info will tell.