As far as I can tell by your url - you have a pdf, not an image. Typically, WebView are used to display such data.
Update
Your start of NSData too long. You can initiate a URL without providing a formatted string:
NSData *mydata = [[NSData alloc] initWithContentsOfURL:[NSURL URLWithString:tmpImgURLStr]];
I also noticed that your url has no protocol. You can try adding http:// or https:// , and then see what happens. And just in case, check if your logoImg is logoImg connected to the NSImageView in your NIB.
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