Facebook authorize w/permissions request yield "Page Not Found"
Somewhere along the way in the past few weeks, the authorize Facebook call in iOS fails with a "Page Not Found". This happens for any user that has not installed the app or if the app's permissions have changed and the user must approve the additional permissions. This happens whether the Facebook app handles the user authentication or Safari or the popup dialog. All redirect to a "Page Not Found" page.
Digging through the debugger, I found the initial URL request to be (app id replaces "[app_id]") for the login screen:
https://m.facebook.com/dialog/oauth?type=user_agent&display=touch&redirect_uri=fb[app_id]%3A%2F%2Fauthorize&sdk=2&scope=user_location%2Cuser_relationships%2Cemail%2Cpublish_stream%2Coffline_access&client_id=[app_id]
The following URL is being sought by the login attempt (I assume by the URL that the user has insufficient permissions):
http://www.facebook.com/dialog/permissions.request?_path=permissions.request&app_id=[appid]&redirect_uri=fb[appid]%3A%3F%3Fauthorize&sdk=2&display=touch&type=user_agent&fbconnect=1&perms=user_location%2Cuser_relationships%2Cemail%2Cpublish_stream%2Coffline_access&sso=iphone-safari&from_login=1
I've checked that the Bundle ID listed in Xcode is the same as that listed for my app's settings in Facebook.
Because the permissions page is not showing, new users cannot add the app. Old versions of my app that used to work are failing in the same way as well. What could be the problem?
Answer
Okay, I'm feeling a bit stupid.
The problem was that I had Sandboxing turned on in the app settings in the Facebook page. Why the error page was so obtuse is beyond me.
- In Facebook developer settings: https://developers.facebook.com, edit your app settings.
- Select the "Advanced" tab, under "Settings" on the left side.
- Make sure that "Sandbox Mode" is not enabled.