The server URL mentioned as root URL gets embedded into your application while exporting. When you use localhost in your URL you have the PHP server running on the same machine as the the FlashBuilder. So everything works as expected. However when you deploy your application on a device "localhost" refersr to the device itself instead of the machine where PHP server is running. This is the reason why FlashBuilder warns you while exporting your application to use the actual server URL. In the screen shot you have posted you probably have the incorrect WebRoot which does not exist on your machine as FlashBuilder allows you to proceed even when the Root URL is inaccessible. Please try inputting the correct WebRoot and Root URL.
i know WHY Flashbuilder tells me that i have to change the setting when i deploy on the device
my problem ist that i got this error...
and the domain wich i have in the screenshot should only explain how i tried it...
i entered my server url (the real domain) and i entered the folder "app" wich i have created via ftp on my server...
BUT i also get this error (lik in the screenshot)
i think at ROOT URL i cant make lot mistakes .... http://myserver.de or the ip
but i think maybe my web root ist incorrect? i entered here the folder wich is directliy on my server...?
i dont know exactly but i got an error like in the screen