diff --git a/Bloxstrap/App.xaml.cs b/Bloxstrap/App.xaml.cs
index 5083121..691d868 100644
--- a/Bloxstrap/App.xaml.cs
+++ b/Bloxstrap/App.xaml.cs
@@ -181,6 +181,22 @@ namespace Bloxstrap
             }
         }
 
+        public static void AssertWindowsOSVersion()
+        {
+            const string LOG_IDENT = "App::AssertWindowsOSVersion";
+
+            int major = Environment.OSVersion.Version.Major;
+            if (major < 10) // Windows 10 and newer only
+            {
+                Logger.WriteLine(LOG_IDENT, $"Detected unsupported Windows version ({Environment.OSVersion.Version}).");
+
+                if (!LaunchSettings.QuietFlag.Active)
+                    Frontend.ShowMessageBox(Strings.App_OSDeprecation_Win7_81, MessageBoxImage.Error);
+
+                Terminate(ErrorCode.ERROR_INVALID_FUNCTION);
+            }
+        }
+
         protected override void OnStartup(StartupEventArgs e)
         {
             const string LOG_IDENT = "App::OnStartup";
@@ -213,6 +229,8 @@ namespace Bloxstrap
 #endif
             }
 
+            Logger.WriteLine(LOG_IDENT, $"OSVersion: {Environment.OSVersion}");
+
             Logger.WriteLine(LOG_IDENT, $"Loaded from {Paths.Process}");
             Logger.WriteLine(LOG_IDENT, $"Temp path is {Paths.Temp}");
             Logger.WriteLine(LOG_IDENT, $"WindowsStartMenu path is {Paths.WindowsStartMenu}");
@@ -292,6 +310,7 @@ namespace Bloxstrap
             {
                 Logger.Initialize(true);
                 Logger.WriteLine(LOG_IDENT, "Not installed, launching the installer");
+                AssertWindowsOSVersion(); // prevent new installs from unsupported operating systems
                 LaunchHandler.LaunchInstaller();
             }
             else
diff --git a/Bloxstrap/Bootstrapper.cs b/Bloxstrap/Bootstrapper.cs
index ea0cd74..e42ff98 100644
--- a/Bloxstrap/Bootstrapper.cs
+++ b/Bloxstrap/Bootstrapper.cs
@@ -179,6 +179,8 @@ namespace Bloxstrap
             }
 #endif
 
+            App.AssertWindowsOSVersion();
+
             // ensure only one instance of the bootstrapper is running at the time
             // so that we don't have stuff like two updates happening simultaneously
 
diff --git a/Bloxstrap/Resources/Strings.Designer.cs b/Bloxstrap/Resources/Strings.Designer.cs
index fd14b8f..d1277a1 100644
--- a/Bloxstrap/Resources/Strings.Designer.cs
+++ b/Bloxstrap/Resources/Strings.Designer.cs
@@ -151,6 +151,15 @@ namespace Bloxstrap.Resources {
             }
         }
         
+        /// <summary>
+        ///   Looks up a localized string similar to Roblox no longer supports Windows 7 or 8.1. To continue playing Roblox, please upgrade to Windows 10 or newer..
+        /// </summary>
+        public static string App_OSDeprecation_Win7_81 {
+            get {
+                return ResourceManager.GetString("App.OSDeprecation.Win7_81", resourceCulture);
+            }
+        }
+        
         /// <summary>
         ///   Looks up a localized string similar to Bloxstrap was unable to automatically update to version {0}. Please update it manually by downloading and running it from the website..
         /// </summary>
diff --git a/Bloxstrap/Resources/Strings.resx b/Bloxstrap/Resources/Strings.resx
index c8a5479..4f3dadb 100644
--- a/Bloxstrap/Resources/Strings.resx
+++ b/Bloxstrap/Resources/Strings.resx
@@ -1267,4 +1267,7 @@ Please close any applications that may be using Roblox's files, and relaunch.</v
     <value>All Bloxstrap logs</value>
     <comment>Label that appears next to a checkbox</comment>
   </data>
+  <data name="App.OSDeprecation.Win7_81" xml:space="preserve">
+    <value>Roblox no longer supports Windows 7 or 8.1. To continue playing Roblox, please upgrade to Windows 10 or newer.</value>
+  </data>
 </root>
\ No newline at end of file