Thanks for your advice,but I'm sure my router configuration is right,because I have try all the config in my router. I'm in school now,but if I'm at home,I can easily connect to my wifi with the same router and same configuration. Maybe it's because my school forbid some website and server.And I also read this from:
http://info.iet.unipi.it/~luigi/kindle/
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The kindle often complains that it cannot connect to a WiFi network, but what this really means is that it cannot connect to amazon.com, and this blocks the browser even if local connectivity is available.
To make the system believe that the network is reachable (and let the browser work), you can issue the following command:
dbus-send --system /default com.lab126.wifid.cmConnected
and you will see the [Wi-Fi] icon turn on.
Unfortunately you need to do it every minute or so, because the daemon in charge of connectivity (wifid or probably the 3G equivalent as well) periodically tries to refresh the address and connect to amazon, and on failure it issues a
dbus-send --system /default com.lab126.wifid.cmNotconnected
event which blocks the browser again.
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but I don't think it's a good method, I can't use the SCP to execute this command.
Maybe can solve this problem by changing the config file in the "/opt/amazon/ebook/config/"