I have a program that I run in C# that goes to a website and in order to do its functions, I need to get the source code of the page.

Code:
System.Net.WebClient webClient = new System.Net.WebClient();
string strSource = webClient.DownloadString(URL);
webClient.Dispose();
return strSource;
Very recently, some of the pages return a [] character while others return the full source code of the page. When I go to the pages outside of my programming, the source code can be seen just as they should.

Why would this be happening and is there a way around this?