Мне нужно разобрать xml-файл из URL-адреса, защищенного паролем. Я пробовал следующее

NSURLCredential *credential = [NSURLCredential credentialWithUser:@"admin"  password:@"123456" persistence:NSURLCredentialPersistenceForSession];
NSURLProtectionSpace *protectionSpace = [[NSURLProtectionSpace alloc]
                                         initWithHost:@"xyz.com"
                                         port:80
                                         protocol:@"http"
                                         realm:nil
                                         authenticationMethod:NSURLAuthenticationMethodDefault];  
[[NSURLCredentialStorage sharedCredentialStorage] setCredential:credential
                                             forProtectionSpace:protectionSpace];    
url = [NSURL URLWithString:urlString];
NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url];
[request setHTTPMethod:@"GET"];
[request setValue:@"application/xml" forHTTPHeaderField:@"Content-Type"];
connection = [[NSURLConnection alloc] initWithRequest:request delegate:self];
NSURLResponse *response;
NSError *error;
NSData *returnData = [NSURLConnection sendSynchronousRequest:request returningResponse: &response error: &error];   
 NSString *dataStr=[[NSString alloc]initWithData:returnData encoding:NSUTF8StringEncoding]; 
 NSLog(@"data == %@\n error in connecting == %@",dataStr,error);

Я получил следующий ответ

data == 



Authorization Required
This server could not verify that you
are authorized to access the document
requested.  Either you supplied the wrong
credentials (e.g., bad password), or your
browser doesn't understand how to supply
the credentials required.
Additionally, a 401 Authorization Required
error was encountered while trying to use an ErrorDocument to handle the request.

ошибка при подключении == Error Domain=NSURLErrorDomain Code= -1012 "Операция не может быть завершена. (Ошибка NSURLErrorDomain -1012. )" UserInfo=0x6e51b90 {NSErrorFailingURLKey=http://example.com/api/ID/password/xml/,

Любая помощь приветствуется!