presentViewController shows black page

Incase anyone else finds this, make sure you haven't set self.view.backgroundColor = UIColor.clearColor() in the view to be shown... This solved it for me.

You are not entering the nib name for the user Interface:

SuccessOrFailViewController *sfvc = [[SuccessOrFailViewController alloc] initWithNibName:@"SuccessOrFailViewController" bundle:nil];
[self presentViewController:sfvc animated:NO completion:NULL];

For storyboard this is the way to go:

UIStoryboard *storyboard = [UIStoryboard storyboardWithName:@"MainStoryboard" bundle:nil];
SuccessOrFailViewController *sfvc = [storyboard instantiateViewControllerWithIdentifier:@"SuccessOrFailViewController"];
[sfvc setModalPresentationStyle:UIModalPresentationFullScreen];
[self presentModalViewController:sfvc animated:YES];

Swift

var next = self.storyboard?.instantiateViewControllerWithIdentifier("DashboardController") as! DashboardController
self.presentViewController(next, animated: true, completion: nil)

don't forget to set ViewController StoryBoard Id in StoryBoard -> identity inspector

For Storyboard iOS7

UIStoryboard *storyboard = [UIStoryboard storyboardWithName:@"MainStoryboard" bundle:nil];
SuccessOrFailViewController *sfvc = [storyboard instantiateViewControllerWithIdentifier:@"SuccessOrFailViewController"];
[sfvc setModalPresentationStyle:UIModalPresentationFullScreen];
[self presentViewController:sfvc animated:YES completion:nil];