diff --git a/docs/release-notes.md b/docs/release-notes.md
index e71457af..a00c73da 100644
--- a/docs/release-notes.md
+++ b/docs/release-notes.md
@@ -3,6 +3,7 @@
 # Release notes
 ## Upcoming release
 * For players:
+  * Added friendly error in 64-bit mode when a mod is 32-bit only.
   * Fixed some installer errors now show info header.
 
 * For mod authors:
diff --git a/src/SMAPI.Toolkit/Framework/LowLevelEnvironmentUtility.cs b/src/SMAPI.Toolkit/Framework/LowLevelEnvironmentUtility.cs
index be0c18ce..2636aae0 100644
--- a/src/SMAPI.Toolkit/Framework/LowLevelEnvironmentUtility.cs
+++ b/src/SMAPI.Toolkit/Framework/LowLevelEnvironmentUtility.cs
@@ -90,10 +90,10 @@ namespace StardewModdingAPI.Toolkit.Framework
         }
 
         /// <summary>Get whether an executable is 64-bit.</summary>
-        /// <param name="executablePath">The absolute path to the executable file.</param>
-        public static bool Is64BitAssembly(string executablePath)
+        /// <param name="path">The absolute path to the assembly file.</param>
+        public static bool Is64BitAssembly(string path)
         {
-            return AssemblyName.GetAssemblyName(executablePath).ProcessorArchitecture != ProcessorArchitecture.X86;
+            return AssemblyName.GetAssemblyName(path).ProcessorArchitecture != ProcessorArchitecture.X86;
         }
 
 
diff --git a/src/SMAPI.Toolkit/Utilities/EnvironmentUtility.cs b/src/SMAPI.Toolkit/Utilities/EnvironmentUtility.cs
index 62bd13cd..6de79a85 100644
--- a/src/SMAPI.Toolkit/Utilities/EnvironmentUtility.cs
+++ b/src/SMAPI.Toolkit/Utilities/EnvironmentUtility.cs
@@ -46,5 +46,12 @@ namespace StardewModdingAPI.Toolkit.Utilities
         {
             return LowLevelEnvironmentUtility.GetExecutableName(platform.ToString());
         }
+
+        /// <summary>Get whether an executable is 64-bit.</summary>
+        /// <param name="path">The absolute path to the assembly file.</param>
+        public static bool Is64BitAssembly(string path)
+        {
+            return LowLevelEnvironmentUtility.Is64BitAssembly(path);
+        }
     }
 }
diff --git a/src/SMAPI/Framework/SCore.cs b/src/SMAPI/Framework/SCore.cs
index 5fb4aa03..dff0fc55 100644
--- a/src/SMAPI/Framework/SCore.cs
+++ b/src/SMAPI/Framework/SCore.cs
@@ -1704,12 +1704,21 @@ namespace StardewModdingAPI.Framework
             // load as mod
             else
             {
+                // get mod info
                 IManifest manifest = mod.Manifest;
+                string assemblyPath = Path.Combine(mod.DirectoryPath, manifest.EntryDll);
+
+                // assert 64-bit
+#if SMAPI_FOR_WINDOWS_64BIT_HACK
+                if (!EnvironmentUtility.Is64BitAssembly(assemblyPath))
+                {
+                    errorReasonPhrase = "it needs to be updated for 64-bit mode.";
+                    failReason = ModFailReason.LoadFailed;
+                    return false;
+                }
+#endif
 
                 // load mod
-                string assemblyPath = manifest?.EntryDll != null
-                    ? Path.Combine(mod.DirectoryPath, manifest.EntryDll)
-                    : null;
                 Assembly modAssembly;
                 try
                 {