Switched back to using Uri.EscapeDataString after some further research; Code cleanup;

Author: Michael Hallett

RestSharp/Extensions/StringExtensions.cs

@@ -55,7 +55,7 @@ public static string UrlEncode(this string input)
                 throw new ArgumentNullException("input");
 
             if (input.Length <= maxLength)
-                return Uri.EscapeUriString(input);
+                return Uri.EscapeDataString(input);
 
             StringBuilder sb = new StringBuilder(input.Length * 2);
             int index = 0;
@@ -65,7 +65,7 @@ public static string UrlEncode(this string input)
                 int length = Math.Min(input.Length - index, maxLength);
                 string subString = input.Substring(index, length);
 
-                sb.Append(Uri.EscapeUriString(subString));
+                sb.Append(Uri.EscapeDataString(subString));
                 index += subString.Length;
             }
 

RestSharp/Http.cs

@@ -19,7 +19,6 @@
 using System.IO;
 using System.Linq;
 using System.Net;
-using System.Security.Cryptography.X509Certificates;
 using System.Text;
 using RestSharp.Extensions;