title: iOS 6 - Facebook sharing procedure fails with error "The proxied app is not already installed"
body: <p>Though, there is such a question <a href="https://stackoverflow.com/questions/12498972/facebook-error-7-ios-6">Facebook Error (7) iOS 6</a> it's already closed without any answer!
  While obtaining an access to user's facebook account I've got an error:
  <code>error is: Error Domain=com.apple.accounts Code=7 "The Facebook server could not fulfill this access request: The proxied app is not already installed." UserInfo=0xa260270 {NSLocalizedDescription=The Facebook server could not fulfill this access request: The proxied app is not already installed.}</code></p>
  
  <p>I'm performing a request like this:</p>
  
  <pre><code>self.statusLabel.text = @"Waiting for authorization...";
  if (self.accountStore == nil) {
      self.accountStore = [[ACAccountStore alloc] init];
  }   
  ACAccountType * facebookAccountType = [self.accountStore accountTypeWithAccountTypeIdentifier:ACAccountTypeIdentifierFacebook];
  
  NSDictionary * dict = @{ACFacebookAppIdKey : FB_APP_ID, ACFacebookAudienceKey : ACFacebookAudienceEveryone};
  [self.accountStore requestAccessToAccountsWithType:facebookAccountType options:dict completion:^(BOOL granted, NSError *error) {
      __block NSString * statusText = nil;
      if (granted) {
          statusText = @"Logged in";
          NSArray * accounts = [self.accountStore accountsWithAccountType:facebookAccountType];
          self.facebookAccount = [accounts lastObject];
          NSLog(@"account is: %@", self.facebookAccount);
          self.statusLabel.text = statusText;
          [self postToFeed];
      }
      else {
          self.statusLabel.text = @"Login failed";
          NSLog(@"error is: %@", error);
      }
  }];
  </code></pre>
  
  <p>What does this error means?</p>