Cannot authorize in Facebook. Android SDK

I'm writing an Android app that allows to post messages to facebook. When I try to login the facebook's page displays an error:

"An error occured". Please try again later"

I tried t开发者_JAVA技巧o use a lot of examples but none of them works. I assume that something is wrong in configuration of the app on facebook. I did not fill the Canvas Page, Canvas URL and Credits Callback URL fields when I was registering it. Is that the reason of the problem?

Thanks. Roman

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Make sure you've set your Android key hash under the "Mobile and Devices" tab in the Facebook app's settings. You will have problems posting if you do not set this correctly. This is explained in detail on the Facebook Developer site.