bpo-41412 and bpo-40948: Windows installer updates (GH-21656)

Prevent installation on Windows 8 and earlier.
Download UCRT on demand when required (non-updated Windows 8.1 only)
Add reference to py launcher to post-install message
(cherry picked from commit 37a06cbe5c17c2aa6ad938339fd42531a8a0bea0)

Co-authored-by: Steve Dower <steve.dower@python.org>

6 files changed, 25 insertions, 69 deletions

diff --git a/Misc/NEWS.d/next/Windows/2020-07-28-11-55-43.bpo-41412.ME20KB.rst b/Misc/NEWS.d/next/Windows/2020-07-28-11-55-43.bpo-41412.ME20KB.rst
new file mode 100644
index 0000000000..274264ad87
--- /dev/null
+++ b/Misc/NEWS.d/next/Windows/2020-07-28-11-55-43.bpo-41412.ME20KB.rst
@@ -0,0 +1,2 @@
+The installer will now fail to install on Windows 7 and Windows 8. Further,
+the UCRT dependency is now always downloaded on demand.
diff --git a/Misc/NEWS.d/next/Windows/2020-07-28-12-39-32.bpo-40948.ISUFO6.rst b/Misc/NEWS.d/next/Windows/2020-07-28-12-39-32.bpo-40948.ISUFO6.rst
new file mode 100644
index 0000000000..f8831d8c13
--- /dev/null
+++ b/Misc/NEWS.d/next/Windows/2020-07-28-12-39-32.bpo-40948.ISUFO6.rst
@@ -0,0 +1 @@
+Improve post-install message to direct people to the "py" command.
diff --git a/Tools/msi/bundle/Default.thm b/Tools/msi/bundle/Default.thm
index 1c0bd08eec..7c37d2cafb 100644
--- a/Tools/msi/bundle/Default.thm
+++ b/Tools/msi/bundle/Default.thm
@@ -116,7 +116,7 @@
         <Text X="185" Y="11" Width="-11" Height="36" FontId="1" DisablePrefix="yes">#(loc.SuccessHeader)</Text>
         <Image X="0" Y="0" Width="178" Height="382" ImageFile="SideBar.png"/>
 
-        <Hypertext Name="SuccessText" X="205" Y="71" Width="-71" Height="150" FontId="3" DisablePrefix="yes"></Hypertext>
+        <Hypertext Name="SuccessText" X="205" Y="71" Width="-71" Height="180" FontId="3" DisablePrefix="yes"></Hypertext>
 
         <Button Name="SuccessMaxPathButton" X="185" Y="-70" Width="-11" Height="81" TabStop="yes" FontId="3" HexStyle="0xE" HideWhenDisabled="yes">#(loc.SuccessMaxPathButton)</Button>
 
diff --git a/Tools/msi/bundle/Default.wxl b/Tools/msi/bundle/Default.wxl
index 43506d6100..f0088d4e13 100644
--- a/Tools/msi/bundle/Default.wxl
+++ b/Tools/msi/bundle/Default.wxl
@@ -89,7 +89,7 @@ Select Customize to review current options.</String>
   <String Id="ShortInstallLauncherAllUsersLabel">Install &amp;launcher for all users (recommended)</String>
   <String Id="PrecompileLabel">&amp;Precompile standard library</String>
   <String Id="Include_symbolsLabel">Download debugging &amp;symbols</String>
-  <String Id="Include_debugLabel">Download debu&amp;g binaries (requires VS 2015 or later)</String>
+  <String Id="Include_debugLabel">Download debu&amp;g binaries (requires VS 2017 or later)</String>
   
   <String Id="ProgressHeader">[ActionLikeInstallation] Progress</String>
   <String Id="ProgressLabel">[ActionLikeInstalling]:</String>
@@ -105,11 +105,11 @@ Select Customize to review current options.</String>
   <String Id="SuccessLaunchButton">&amp;Launch</String>
   <String Id="SuccessRestartText">You may need to restart your computer to finish updating files.</String>
   <String Id="SuccessRestartButton">&amp;Restart</String>
-  <String Id="SuccessInstallMessage">Special thanks to Mark Hammond, without whose years of freely shared Windows expertise, Python for Windows would still be Python for DOS.
+  <String Id="SuccessInstallMessage">New to Python? Start with the &lt;a href="https://docs.python.org/[ShortVersion]/tutorial/index.html"&gt;online tutorial&lt;/a&gt; and &lt;a href="https://docs.python.org/[ShortVersion]/index.html"&gt;documentation&lt;/a&gt;. At your terminal, type "py" to launch Python, or search for Python in your Start menu.
 
-New to Python? Start with the &lt;a href="https://docs.python.org/[ShortVersion]/tutorial/index.html"&gt;online tutorial&lt;/a&gt; and &lt;a href="https://docs.python.org/[ShortVersion]/index.html"&gt;documentation&lt;/a&gt;.
+See &lt;a href="https://docs.python.org/[ShortVersion]/whatsnew/[ShortVersion].html"&gt;what's new&lt;/a&gt; in this release, or find more info about &lt;a href="https://docs.python.org/[ShortVersion]/using/windows.html"&gt;using Python on Windows&lt;/a&gt;.
 
-See &lt;a href="https://docs.python.org/[ShortVersion]/whatsnew/[ShortVersion].html"&gt;what's new&lt;/a&gt; in this release.</String>
+Special thanks to Mark Hammond, without whose years of freely shared Windows expertise, Python for Windows would still be Python for DOS.</String>
   <String Id="SuccessModifyMessage">Thank you for using [WixBundleName].</String>
   <String Id="SuccessRepairMessage">Thank you for using [WixBundleName].
 
@@ -123,26 +123,9 @@ Feel free to email &lt;a href="mailto:python-list@python.org"&gt;python-list@pyt
   <String Id="FailureRestartButton">&amp;Restart</String>
   <String Id="FailureExistingInstall">Unable to install [WixBundleName] due to an existing install. Use Programs and Features to modify, repair or remove [WixBundleName].</String>
   
-  <String Id="FailureWin7MissingSP1">Windows 7 Service Pack 1 and all applicable updates are required to install [WixBundleName].
-
-Please &lt;a href="https://www.bing.com/search?q=how%20to%20install%20windows%207%20service%20pack%201"&gt;update your machine&lt;/a&gt; and then restart the installation.</String>
-  <String Id="FailureVistaMissingSP2">Windows Vista Service Pack 2 and all applicable updates are required to install [WixBundleName].
-
-Please &lt;a href="https://www.bing.com/search?q=how%20to%20install%20windows%20vista%20service%20pack%202"&gt;update your machine&lt;/a&gt; and then restart the installation.</String>
-  <String Id="FailureXPOrEarlier">Windows Vista or later is required to install and use [WixBundleName].
-
-Visit &lt;a href="https://www.python.org/"&gt;python.org&lt;/a&gt; to download Python 3.4.</String>
-
-  <String Id="FailureWS2K8R2MissingSP1">Windows Server 2008 R2 Service Pack 1 and all applicable updates are required to install [WixBundleName].
-
-Please &lt;a href="https://www.bing.com/search?q=how%20to%20install%20windows%20server%202008%20r2%20service%20pack%201"&gt;update your machine&lt;/a&gt; and then restart the installation.</String>
-  <String Id="FailureWS2K8MissingSP2">Windows Server 2008 Service Pack 2 and all applicable updates are required to install [WixBundleName].
-
-Please &lt;a href="https://www.bing.com/search?q=how%20to%20install%20windows%20server%202008%20service%20pack%202"&gt;update your machine&lt;/a&gt; and then restart the installation.</String>
-  <String Id="FailureWS2K3OrEarlier">Windows Server 2008 SP2 or later is required to install and use [WixBundleName].
-
-Visit &lt;a href="https://www.python.org/"&gt;python.org&lt;/a&gt; to download Python 3.4.</String>
+  <String Id="FailureOldOS">At least Windows 8.1 or Windows Server 2012 are required to install [WixBundleName]
 
+Visit &lt;a href="https://www.python.org/"&gt;python.org&lt;/a&gt; to download an earlier version of Python.</String>
   <String Id="SuccessMaxPathButton">Disable path length limit</String>
   <String Id="SuccessMaxPathButtonNote">Changes your machine configuration to allow programs, including Python, to bypass the 260 character "MAX_PATH" limitation.</String>
 </WixLocalization>
diff --git a/Tools/msi/bundle/bootstrap/PythonBootstrapperApplication.cpp b/Tools/msi/bundle/bootstrap/PythonBootstrapperApplication.cpp
index fbdf7b6424..3c54e40133 100644
--- a/Tools/msi/bundle/bootstrap/PythonBootstrapperApplication.cpp
+++ b/Tools/msi/bundle/bootstrap/PythonBootstrapperApplication.cpp
@@ -3011,65 +3011,35 @@ private:
                 BalLog(BOOTSTRAPPER_LOG_LEVEL_STANDARD, "Target OS is Windows Server 2012 or later");
                 return;
             } else if (IsWindowsVersionOrGreater(6, 1, 1)) {
-                HMODULE hKernel32 = GetModuleHandleW(L"kernel32");
-                if (hKernel32 && !GetProcAddress(hKernel32, "AddDllDirectory")) {
-                    BalLog(BOOTSTRAPPER_LOG_LEVEL_ERROR, "Detected Windows Server 2008 R2 without KB2533623");
-                    BalLog(BOOTSTRAPPER_LOG_LEVEL_ERROR, "KB2533623 update is required to continue.");
-                    /* The "MissingSP1" error also specifies updates are required */
-                    LocGetString(_wixLoc, L"#(loc.FailureWS2K8R2MissingSP1)", &pLocString);
-                } else {
-                    BalLog(BOOTSTRAPPER_LOG_LEVEL_STANDARD, "Target OS is Windows Server 2008 R2 or later");
-                    return;
-                }
+                BalLog(BOOTSTRAPPER_LOG_LEVEL_STANDARD, "Detected Windows Server 2008 R2");
             } else if (IsWindowsVersionOrGreater(6, 1, 0)) {
                 BalLog(BOOTSTRAPPER_LOG_LEVEL_ERROR, "Detected Windows Server 2008 R2");
-                BalLog(BOOTSTRAPPER_LOG_LEVEL_ERROR, "Service Pack 1 is required to continue installation");
-                LocGetString(_wixLoc, L"#(loc.FailureWS2K8R2MissingSP1)", &pLocString);
-            } else if (IsWindowsVersionOrGreater(6, 0, 2)) {
-                BalLog(BOOTSTRAPPER_LOG_LEVEL_ERROR, "Target OS is Windows Server 2008 SP2 or later");
-                return;
             } else if (IsWindowsVersionOrGreater(6, 0, 0)) {
                 BalLog(BOOTSTRAPPER_LOG_LEVEL_ERROR, "Detected Windows Server 2008");
-                BalLog(BOOTSTRAPPER_LOG_LEVEL_ERROR, "Service Pack 2 is required to continue installation");
-                LocGetString(_wixLoc, L"#(loc.FailureWS2K8MissingSP2)", &pLocString);
             } else {
                 BalLog(BOOTSTRAPPER_LOG_LEVEL_ERROR, "Detected Windows Server 2003 or earlier");
-                BalLog(BOOTSTRAPPER_LOG_LEVEL_ERROR, "Windows Server 2008 SP2 or later is required to continue installation");
-                LocGetString(_wixLoc, L"#(loc.FailureWS2K3OrEarlier)", &pLocString);
             }
+            BalLog(BOOTSTRAPPER_LOG_LEVEL_ERROR, "Windows Server 2012 or later is required to continue installation");
         } else {
-            if (IsWindows8OrGreater()) {
-                BalLog(BOOTSTRAPPER_LOG_LEVEL_STANDARD, "Target OS is Windows 8 or later");
+            if (IsWindows10OrGreater()) {
+                BalLog(BOOTSTRAPPER_LOG_LEVEL_STANDARD, "Target OS is Windows 10 or later");
                 return;
-            } else if (IsWindows7SP1OrGreater()) {
-                HMODULE hKernel32 = GetModuleHandleW(L"kernel32");
-                if (hKernel32 && !GetProcAddress(hKernel32, "AddDllDirectory")) {
-                    BalLog(BOOTSTRAPPER_LOG_LEVEL_ERROR, "Detected Windows 7 SP1 without KB2533623");
-                    BalLog(BOOTSTRAPPER_LOG_LEVEL_ERROR, "KB2533623 update is required to continue.");
-                    /* The "MissingSP1" error also specifies updates are required */
-                    LocGetString(_wixLoc, L"#(loc.FailureWin7MissingSP1)", &pLocString);
-                } else {
-                    BalLog(BOOTSTRAPPER_LOG_LEVEL_STANDARD, "Target OS is Windows 7 SP1 or later");
-                    return;
-                }
-            } else if (IsWindows7OrGreater()) {
-                BalLog(BOOTSTRAPPER_LOG_LEVEL_ERROR, "Detected Windows 7 RTM");
-                BalLog(BOOTSTRAPPER_LOG_LEVEL_ERROR, "Service Pack 1 is required to continue installation");
-                LocGetString(_wixLoc, L"#(loc.FailureWin7MissingSP1)", &pLocString);
-            } else if (IsWindowsVistaSP2OrGreater()) {
-                BalLog(BOOTSTRAPPER_LOG_LEVEL_ERROR, "Target OS is Windows Vista SP2");
+            } else if (IsWindows8Point1OrGreater()) {
+                BalLog(BOOTSTRAPPER_LOG_LEVEL_STANDARD, "Target OS is Windows 8.1");
                 return;
+            } else if (IsWindows8OrGreater()) {
+                BalLog(BOOTSTRAPPER_LOG_LEVEL_ERROR, "Detected Windows 8");
+            } else if (IsWindows7OrGreater()) {
+                BalLog(BOOTSTRAPPER_LOG_LEVEL_ERROR, "Detected Windows 7");
             } else if (IsWindowsVistaOrGreater()) {
-                BalLog(BOOTSTRAPPER_LOG_LEVEL_ERROR, "Detected Windows Vista RTM or SP1");
-                BalLog(BOOTSTRAPPER_LOG_LEVEL_ERROR, "Service Pack 2 is required to continue installation");
-                LocGetString(_wixLoc, L"#(loc.FailureVistaMissingSP2)", &pLocString);
+                BalLog(BOOTSTRAPPER_LOG_LEVEL_ERROR, "Detected Windows Vista");
             } else { 
                 BalLog(BOOTSTRAPPER_LOG_LEVEL_ERROR, "Detected Windows XP or earlier");
-                BalLog(BOOTSTRAPPER_LOG_LEVEL_ERROR, "Windows Vista SP2 or later is required to continue installation");
-                LocGetString(_wixLoc, L"#(loc.FailureXPOrEarlier)", &pLocString);
             }
+            BalLog(BOOTSTRAPPER_LOG_LEVEL_ERROR, "Windows 8.1 or later is required to continue installation");
         }
 
+        LocGetString(_wixLoc, L"#(loc.FailureOldOS)", &pLocString);
         if (pLocString && pLocString->wzText) {
             BalFormatString(pLocString->wzText, &_failedMessage);
         }
diff --git a/Tools/msi/bundle/packagegroups/crt.wxs b/Tools/msi/bundle/packagegroups/crt.wxs
index 61b756fc25..f931da1403 100644
--- a/Tools/msi/bundle/packagegroups/crt.wxs
+++ b/Tools/msi/bundle/packagegroups/crt.wxs
@@ -4,7 +4,7 @@
         <PackageGroup Id="crt">
             <MsiPackage Id="ucrt_AllUsers"
                         SourceFile="ucrt.msi"
-                        Compressed="$(var.CompressMSI)"
+                        Compressed="no"
                         DownloadUrl="$(var.DownloadUrl)"
                         ForcePerMachine="yes"
                         InstallCondition="InstallAllUsers and not CRTInstalled and (Include_core or Include_exe or Include_pip) and not LauncherOnly">
@@ -12,7 +12,7 @@
             </MsiPackage>
             <MsiPackage Id="ucrt_JustForMe"
                         SourceFile="ucrt.msi"
-                        Compressed="$(var.CompressMSI)"
+                        Compressed="no"
                         DownloadUrl="$(var.DownloadUrl)"
                         ForcePerMachine="no"
                         InstallCondition="not InstallAllUsers and not CRTInstalled and (Include_core or Include_exe or Include_pip) and not LauncherOnly">