presentViewController:animated:completion: is available on iOS5 and above only, hence you get that crash.

 presentViewController:animated:completion: is available on iOS5 and above only, hence you get that crash.

Change the last part to:

if ([MFMailComposeViewController canSendMail]) 

        {

            UIImage *tempImageSave=[self captureView];

            //                imgBackBoard.image = [self captureView];

            //                [imgBackBoard.image retain];

            MFMailComposeViewController *mailComposeViewController = [[MFMailComposeViewController alloc] init];

            NSString *mailBody = @"New Image Of Retreat Caravans Posted By Paras";

            

            NSData *imageData = UIImagePNGRepresentation(tempImageSave);

            [mailComposeViewController addAttachmentData:imageData mimeType:@"image/png" fileName:@"Testing"];

            [mailComposeViewController setMessageBody:mailBody isHTML:NO];

            mailComposeViewController.mailComposeDelegate = self;

            if ([self respondsToSelector:@selector(presentViewController:animated:completion:)])

            {   //yes->so do it!

                [self presentViewController:mailComposeViewController animated:YES completion:NULL];

            }

            else

            {   //nope->we seem to be running on something prior to iOS5, do it the old way!

                [self presentModalViewController:mailComposeViewController animated:YES];

            }

//            [self presentViewController:mailComposeViewController animated:YES completion:nil];

        } 

        else 

        {

            UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"e-Mail Sending Alert"

                                                            message:@"You can't send a mail"

                                                           delegate:nil

                                                  cancelButtonTitle:@"OK" 

                                                  otherButtonTitles:nil];

            [alert show];

            [alert release];

        }

Also dissmis like above..
For EX..

if([self respondsToSelector:@selector(dismissViewControllerAnimated:completion:)])

        [self dismissViewControllerAnimated:YES completion:nil];

    else

        [self dismissModalViewControllerAnimated:YES];

This will first check if the new way of presenting a viewController is supported. For making sure that this works fine in the future, as presentModalViewController: is marked as being deprecated, we only use that option if the new way is not available.