iOS HTTP posting not working with shared server - ios

Question

Hi I am working on an iOS app, from this there is a http post method for signup. This method is working perfectly fine with a dedicated server. But fails with a shared server.
There is no fail report in HTTP posting delegates (NSURLConnection), however the "didfinish" delegate is being called too. But the problem is no data is arrived in server side, we are posting plenty of details with an image - but nothing reached at server side.
In android same posting with same server is working fine without an issue.
What could be the reason. Please help me to fix this.
Here is the code for posting.
-(void)postMethod{
NSString *urlString =#"http://sharedserverurl.com";
NSMutableURLRequest *request= [[NSMutableURLRequest alloc] init];
[request setURL:[NSURL URLWithString:urlString]];
[request setHTTPMethod:#"POST"];
NSString *boundary = #"---------------------------14737809831466499882746641449";
NSString *contentType = [NSString stringWithFormat:#"multipart/form-data; boundary=%#",boundary];
[request addValue:contentType forHTTPHeaderField: #"Content-Type"];
NSMutableData *postbody = [NSMutableData data];
[postbody appendData:[[NSString stringWithFormat:#"\r\n--%#\r\n",boundary] dataUsingEncoding:NSUTF8StringEncoding]];
//Sending user_name
[postbody appendData:[[NSString stringWithFormat:#"Content-Disposition: form-data; name=\"username\"\r\n\r\n%#", user_name.text] dataUsingEncoding:NSUTF8StringEncoding]];
[postbody appendData:[[NSString stringWithFormat:#"\r\n--%#\r\n",boundary] dataUsingEncoding:NSUTF8StringEncoding]];
//Sending user_id
[postbody appendData:[[NSString stringWithFormat:#"Content-Disposition: form-data; name=\"user_id\"\r\n\r\n%#", user_id.text] dataUsingEncoding:NSUTF8StringEncoding]];
[postbody appendData:[[NSString stringWithFormat:#"\r\n--%#\r\n",boundary] dataUsingEncoding:NSUTF8StringEncoding]];
//Sending userImage
[postbody appendData:[[NSString stringWithFormat:#"Content-Disposition: form-data; name=\"image\"; filename=\"userimage.png\"\r\n"] dataUsingEncoding:NSUTF8StringEncoding]];
[postbody appendData:[#"Content-Type: application/octet-stream\r\n\r\n" dataUsingEncoding:NSUTF8StringEncoding]];
[postbody appendData:[NSData dataWithData:file]];
[postbody appendData:[[NSString stringWithFormat:#"\r\n--%#--\r\n",boundary] dataUsingEncoding:NSUTF8StringEncoding]];
[request setHTTPBody:postbody];
conn = [[NSURLConnection alloc] initWithRequest:request delegate:self];
if (conn) {
webData = [NSMutableData data];
}
}