diff --git a/src/Umbraco.Tests/Cache/CacheRefresherTests.cs b/src/Umbraco.Tests/Cache/CacheRefresherTests.cs
index 2cc84457ae..c5be44dcdd 100644
--- a/src/Umbraco.Tests/Cache/CacheRefresherTests.cs
+++ b/src/Umbraco.Tests/Cache/CacheRefresherTests.cs
@@ -7,10 +7,10 @@ namespace Umbraco.Tests.Cache
     public class CacheRefresherTests
     {
         [TestCase("", "123456", "testmachine", true)] //empty hash will continue
-        [TestCase("2c8aabac795d189d444a9cdc6e2a1819", "123456", "testmachine", false)] //match, don't continue
-        [TestCase("2c8aabac795d189d444a9cdc6e2a1819", "12345", "testmachine", true)]
-        [TestCase("2c8aabac795d189d444a9cdc6e2a1819", "123456", "testmachin", true)]
-        [TestCase("2c8aabac795d189d444a9cdc6e2a181", "123456", "testmachine", true)]
+        [TestCase("fffffff28449cf33", "123456", "testmachine", false)] //match, don't continue
+        [TestCase("fffffff28449cf33", "12345", "testmachine", true)]
+        [TestCase("fffffff28449cf33", "123456", "testmachin", true)]
+        [TestCase("fffffff28449cf3", "123456", "testmachine", true)]
         public void Continue_Refreshing_For_Request(string hash, string appDomainAppId, string machineName, bool expected)
         {
             var refresher = new CacheRefresher();
diff --git a/src/Umbraco.Web/umbraco.presentation/umbraco/webservices/CacheRefresher.asmx.cs b/src/Umbraco.Web/umbraco.presentation/umbraco/webservices/CacheRefresher.asmx.cs
index 224b674cba..5bcd3cab79 100644
--- a/src/Umbraco.Web/umbraco.presentation/umbraco/webservices/CacheRefresher.asmx.cs
+++ b/src/Umbraco.Web/umbraco.presentation/umbraco/webservices/CacheRefresher.asmx.cs
@@ -39,7 +39,10 @@ namespace umbraco.presentation.webservices
             // that executed the request.
             if (hash.IsNullOrWhiteSpace() == false && SystemUtilities.GetCurrentTrustLevel() == AspNetHostingPermissionLevel.Unrestricted)
             {
-                var hashedAppId = (machineName + appDomainAppId).ToMd5();
+                var hasher = new HashCodeCombiner();
+                hasher.AddCaseInsensitiveString(machineName);
+                hasher.AddCaseInsensitiveString(appDomainAppId);
+                var hashedAppId = hasher.GetCombinedHashCode();
 
                 //we can only check this in full trust. if it's in medium trust we'll just end up with 
                 // the server refreshing it's cache twice.