diff --git a/source/Calamari.Tests/ArgoCD/Git/AuthenticatingRepositoryFactoryTests.cs b/source/Calamari.Tests/ArgoCD/Git/AuthenticatingRepositoryFactoryTests.cs
index 3d4593717..5d559298f 100644
--- a/source/Calamari.Tests/ArgoCD/Git/AuthenticatingRepositoryFactoryTests.cs
+++ b/source/Calamari.Tests/ArgoCD/Git/AuthenticatingRepositoryFactoryTests.cs
@@ -81,6 +81,8 @@ public void AnonymousCloneWhenNoCredentialsMatch()
     public class SshUrlTests : AuthenticatingRepositoryFactoryTestBase
     {
         [Test]
+        // SSH not currently functional on Windows
+        [Category(TestCategory.CompatibleOS.OnlyNixOrMac)]
         public void SshCredentialBranch_IsSelectedAndDispatchesSshKeyGitConnection()
         {
             // Use an ssh:// URL so the new strict validation allows it, and mock the factory
@@ -108,6 +110,8 @@ public void HttpsCredentialTakesPriorityOverSshWhenBothMatchAnSshUrl()
         }
 
         [Test]
+        // SSH not currently functional on Windows
+        [Category(TestCategory.CompatibleOS.OnlyNixOrMac)]
         public void KnownHostsFromDtoAreCarriedOntoSshKeyGitConnection()
         {
             const string sshUrl = "ssh://git@github.com/org/repo.git";
diff --git a/source/Calamari/ArgoCD/Git/AuthenticatingRepositoryFactory.cs b/source/Calamari/ArgoCD/Git/AuthenticatingRepositoryFactory.cs
index d24b3ee2c..0d65231bc 100644
--- a/source/Calamari/ArgoCD/Git/AuthenticatingRepositoryFactory.cs
+++ b/source/Calamari/ArgoCD/Git/AuthenticatingRepositoryFactory.cs
@@ -1,6 +1,8 @@
 using System;
 using System.Collections.Generic;
 using System.Linq;
+using Calamari.Common.Commands;
+using Calamari.Common.Plumbing;
 using Calamari.Common.Plumbing.Logging;
 using Octopus.Calamari.Contracts.ArgoCD;
 
@@ -29,6 +31,15 @@ public AuthenticatingRepositoryFactory(
     public RepositoryWrapper CloneRepository(string requestedUrl, string targetRevision)
     {
         var gitCredential = gitCredentials.GetValueOrDefault(requestedUrl);
+
+        if (gitCredential is SshKeyGitCredentialDto && CalamariEnvironment.IsRunningOnWindows)
+        {
+            throw new CommandException(
+                $"Cannot clone '{requestedUrl}' using an SSH key credential: "
+                + "SSH git credentials are not supported when Calamari is running on Windows. "
+                + "Supply a username/password credential for this repository, or run the deployment on a Linux worker.");
+        }
+
         switch (gitCredential)
         {
             case GitCredentialDto passwordCredential:
@@ -61,4 +72,4 @@ public RepositoryWrapper CloneRepository(string requestedUrl, string targetRevis
         var anonGitConnection = new HttpsGitConnection(null, null, GitCloneSafeUrl.ConvertToUriString(requestedUrl), GitReference.CreateFromString(targetRevision));
         return repositoryFactory.CloneRepository(UniqueRepoNameGenerator.Generate(), anonGitConnection);
     }
-}
\ No newline at end of file
+}